From brunneraa1p at comcast.net  Sun Nov  1 03:00:33 2020
From: brunneraa1p at comcast.net (Richard)
Date: Sun, 1 Nov 2020 03:00:33 -0500
Subject: [Milsurplus] Question...
In-Reply-To: <5F9E2A5F.17163.27A17E1@kgordon2006.frontier.com>
References: <5F9E2A5F.17163.27A17E1@kgordon2006.frontier.com>
Message-ID: <aba773bf-ac71-ed53-1ac4-9ed43c8a56bb@comcast.net>

Before doing anything, connect a transformer and see what happens.? 
Transformers are pretty tolerant of waveform, as long as there are no 
big spikes.? I've had several generators, waveform was close enough to 
sinusoidal and they worked fine.? Also an inverter with "modified sine 
wave" which was square waves with rounded edges, which also worked fine.

Richard, AA1P

On 10/31/20 11:24 PM, Kenneth G. Gordon wrote:
> At this point, I don't know where else to post this, so here goes:
>
> I have a "small emergency generator", 7500 watts, brand new.
>
> From my reading, I find that the output waveform is very "dirty" as it 
> is some sort of "stepped" square-wave. I have not yet looked at the 
> wave-form with an oscilloscope, but I am not expecting it to be very 
> pretty.
>
> My old military generators output a nearly pure sine wave, but these 
> modern beasts don't.
>
> SO....I have two heavy (about 70 lbs each) 115-115 volt isolation 
> transformers. good for at least 15 amps input/output each.
>
> I propose to "tune" them to 60 Hz by connecting capacitors in such a 
> way as to make them into 60 Hz tuned circuits with the idea that doing 
> so should "round off" the waveforms and eliminate the harmonics.
>
> What does the collective wisdom think of this idea? Has anyone tried 
> this? What was your result?
>
> Ken W7EKB
>
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201101/020acba1/attachment.html>

From ramcam at magma.ca  Sun Nov  1 09:25:32 2020
From: ramcam at magma.ca (Ralph Cameron)
Date: Sun, 1 Nov 2020 09:25:32 -0500
Subject: [Milsurplus] Arc-5 bottom plate
Message-ID: <13759.1604240732@magma.ca>

  BODY { font-family:Arial, Helvetica, sans-serif;font-size:12px;
}Have an ARC-5 Transmitter series bottom plate , free for postage. 
 Ralph, VE3BBM
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201101/8d369e96/attachment.html>

From k1whs at metrocast.net  Sun Nov  1 11:47:59 2020
From: k1whs at metrocast.net (David Olean)
Date: Sun, 1 Nov 2020 11:47:59 -0500
Subject: [Milsurplus] [ARC5] Question...
In-Reply-To: <CADgAsSSG9h9u5J7RMsHyTPGdEhsJMfXRiAA81_mB+A9vVPHRog@mail.gmail.com>
References: <5F9E2A5F.17163.27A17E1@kgordon2006.frontier.com>
	<CADgAsSSG9h9u5J7RMsHyTPGdEhsJMfXRiAA81_mB+A9vVPHRog@mail.gmail.com>
Message-ID: <0a671016-faef-1be3-a386-41963a07e951@metrocast.net>

Then there is the problem of hardware store generators (cheap gasoline 
powered) not supplying exactly 60 Hz. The RPMs slow under load and the 
frequency varies. This can negate benefits from constant voltage 
transformers abit. They want 60.0 Hz to work properly.? Old gensets with 
lots of "iron" tend to have better waveforms. I have seen some inverter 
types that are great. They do produce lots of RFI though.

Dave K1WHS

On 10/31/2020 11:48 PM, Dennis Monticelli wrote:
> Ken,
>
> You have a generator with a quasi sine wave switched mode inverter.? 
> Yes, they're dirty.? My museum has run that type of inverter at street 
> faires?before and the radios have issues.
>
> I don't think resonating a conventional power transformer is a good 
> idea because the circulating currents would be high and it would 
> probably overheat.? You have no doubt run across SOLA ferroresonant 
> line transformers; they are much oversized for their power rating.? I 
> recommend putting both differential and common mode filters on the output.
>
> Dennis AE6C
>
> On Sat, Oct 31, 2020 at 8:25 PM Kenneth G. Gordon 
> <kgordon2006 at frontier.com <mailto:kgordon2006 at frontier.com>> wrote:
>
>     At this point, I don't know where else to post this, so here goes:
>
>     I have a "small emergency generator", 7500 watts, brand new.
>
>     From my reading, I find that the output waveform is very "dirty"
>     as it is some sort of "stepped" square-wave. I have not yet looked
>     at the wave-form with an oscilloscope, but I am not expecting it
>     to be very pretty.
>
>     My old military generators output a nearly pure sine wave, but
>     these modern beasts don't.
>
>     SO....I have two heavy (about 70 lbs each) 115-115 volt isolation
>     transformers. good for at least 15 amps input/output each.
>
>     I propose to "tune" them to 60 Hz by connecting capacitors in such
>     a way as to make them into 60 Hz tuned circuits with the idea that
>     doing so should "round off" the waveforms and eliminate the harmonics.
>
>     What does the collective wisdom think of this idea? Has anyone
>     tried this? What was your result?
>
>     Ken W7EKB
>
>     ______________________________________________________________
>     ARC5 mailing list
>     Home: http://mailman.qth.net/mailman/listinfo/arc5
>     Help: http://mailman.qth.net/mmfaq.htm
>     Post: mailto:ARC5 at mailman.qth.net <mailto:ARC5 at mailman.qth.net>
>
>     This list hosted by: http://www.qsl.net
>     Please help support this email list: https://www.qsl.net/donate.html
>
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201101/255ab2dd/attachment-0001.html>

From mjcal77 at yahoo.com  Sun Nov  1 12:15:40 2020
From: mjcal77 at yahoo.com (CL in NC)
Date: Sun, 1 Nov 2020 17:15:40 +0000 (UTC)
Subject: [Milsurplus] Dirty generators
References: <43461786.714650.1604250940397.ref@mail.yahoo.com>
Message-ID: <43461786.714650.1604250940397@mail.yahoo.com>

Back in the day of the 110VAC/12VDC radio, both tube type and solid state, the DC side was either a vibrator or switching transistors, and their output fed a square wave to the same power transformer as the separate 110VAC primary.  Most of the dirty generators say some where that they are not for electronic equipment, but that would be the modern stuff that has their own switching supplies built in.  If the rig is one with a transformer in it for the PS, perhaps the issue is the receiver picking up through its antenna input, every squeak, tone, and spike the generator is creating.

Charlie, W4MEC in NC

From brunneraa1p at comcast.net  Sun Nov  1 14:23:55 2020
From: brunneraa1p at comcast.net (Richard)
Date: Sun, 1 Nov 2020 14:23:55 -0500
Subject: [Milsurplus] Dirty generators
In-Reply-To: <43461786.714650.1604250940397@mail.yahoo.com>
References: <43461786.714650.1604250940397.ref@mail.yahoo.com>
	<43461786.714650.1604250940397@mail.yahoo.com>
Message-ID: <0cc9b34e-3a29-c092-a147-0a807c4b4df7@comcast.net>

You raise an interesting point.? I've had three gas generators, and none 
radiated radio noise.? conversely, 60-70 years ago in a quiet location 
one could hear car ignition noise a mile or more away.? Back then 
ignition noise was a BIG problem for mobile operation.

Decades ago there was a report in QST about a guy who bought a generator 
for field-day use which promptly burned up his transformers. Examination 
of the waveform showed square waves with huge spikes at the crossover 
points.? My first generator had triangular waves which rounded slightly 
under load. (a saturated pole design, whatever that is)? Transformer 
exciting current was less than on a sine wave, and it worked fine.

Richard, AA1P

On 11/1/20 12:15 PM, CL in NC via Milsurplus wrote:
> Back in the day of the 110VAC/12VDC radio, both tube type and solid state, the DC side was either a vibrator or switching transistors, and their output fed a square wave to the same power transformer as the separate 110VAC primary.  Most of the dirty generators say some where that they are not for electronic equipment, but that would be the modern stuff that has their own switching supplies built in.  If the rig is one with a transformer in it for the PS, perhaps the issue is the receiver picking up through its antenna input, every squeak, tone, and spike the generator is creating.
>
> Charlie, W4MEC in NC
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

From robert.h.goff at gmail.com  Sun Nov  1 19:06:33 2020
From: robert.h.goff at gmail.com (Robert Goff)
Date: Sun, 1 Nov 2020 16:06:33 -0800
Subject: [Milsurplus] TCM on Portland CL
Message-ID: <CAF6Vb57GNmr4mGKePDMM6T-xRg1LKkLnGpi_n9p5cp4+ic1jBw@mail.gmail.com>

I've already got one, otherwise I'd be all over it:

https://portland.craigslist.org/mlt/ele/d/rainier-help-radio-transmitter-navy/7220811961.html

Hopefully one of you can find it a new home.

73,
de Robert W7MKA

From robert.h.goff at gmail.com  Sun Nov  1 20:32:10 2020
From: robert.h.goff at gmail.com (Robert Goff)
Date: Sun, 1 Nov 2020 17:32:10 -0800
Subject: [Milsurplus] FTGH: BC-610 Coils
Message-ID: <CAF6Vb54OZwkKX_yATfr9ADrYfOnSGqy+TP7mY3oSzMHZU7gB3A@mail.gmail.com>

I've got two big boxes of these, with multiples of just about every
coil type.  Catch is the celluloid strips are warped on each and every
one and would need to be rebuilt.

So, if you need coils and are willing to do the rebuilding, send me a
note.  I can probably fit two or three in a flat rate box.

73,
de Robert W7MKA

From arc5 at ix.netcom.com  Sun Nov  1 20:44:27 2020
From: arc5 at ix.netcom.com (David Stinson)
Date: Sun, 1 Nov 2020 19:44:27 -0600
Subject: [Milsurplus] [ARC5] ARC-5 history...
In-Reply-To: <5F9E1875.21792.2341E00@kgordon2006.frontier.com>
References: <20201031170824.9dc1dbc5e88513c455a3a0e0e8518a33.6d510d17f8.wbe@email17.secureserver.net>
	<5F9E1875.21792.2341E00@kgordon2006.frontier.com>
Message-ID: <a815bd47-c84a-9e0f-acd3-839ff52f6a46@ix.netcom.com>

Gordon, if you send me the article
and photos, I? can host them on the web.
Dave S.

On 10/31/2020 9:07 PM, Kenneth G. Gordon wrote:
> On 31 Oct 2020 at 17:08, gewhite at crosslink.net wrote:
>
>>  ??? If anyone on this list? is interested in a? roundup article on Command Set history I wrote
>> back in 1984 please send me your postal address and I?ll send him/her a copy.? It has
>> photos and I do not believe this site accepts attachments.
>>
>> Gordon Eliot White
>> gewhite122 at gmail.com
> Please count me in.
>
> vy 73,
>
> Ken W7EKB

-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


From old_radio at aol.com  Mon Nov  2 02:43:33 2020
From: old_radio at aol.com (Jim Whartenby)
Date: Mon, 2 Nov 2020 07:43:33 +0000 (UTC)
Subject: [Milsurplus] Arc-38A as modified by RCA
In-Reply-To: <914841023.751350.1604273182645@mail.yahoo.com>
References: <1258479195.379.1603969161058@wamui-abby.atl.sa.earthlink.net>
	<06a101d6ae19$91e57dc0$b5b07940$@bellsouth.net>
	<585093689.729142.1604260200512@mail.yahoo.com>
	<914841023.751350.1604273182645@mail.yahoo.com>
Message-ID: <2113409776.795718.1604303013716@mail.yahoo.com>

Mike
I do not agree with you that the ARC-21 had a history of unreliability.? It certainly was not much different then any other system found in the B-47 bomber other then the K Bombing and Navigation System.? This system weighed in at over a thousand pounds and used 370 vacuum tubes and an even higher number of relays.? MTBF for the BNS was so low that spare modules were carried in the B-47 Navigator's compartment.
It is rarely mentioned that the AN/ARC-21 was designed for use in the B-47 where it was mounted in the rear of the aircraft, aft of the rear landing gear, along with the ARC-27 UHF transceiver.? This location is where vibration and temperature extremes work it's magic.? Any HF transceivers used in place of the ARC-21 were installed in support aircraft such as the KC-97 or KC-135, not in a B-47.? No other HF transceiver available at this time was able to operate under the extreme conditions found in the B-47.??
The ARC-21 did have initial teething problems not unlike many other "state of the art" systems found in the B-47 or other aircraft.? But these problems were addressed and corrected as the source of the problems were determined and the failure mechanisms understood.? This was verified in the final report of "Project Big Eva" An Accelerated Service Test of Radio Set AN/ARC-21 in March, 1955.
There were two U.S. Congressional investigations concerning the ARC-21 of which I am aware.? The first was titled "Air Force Development and Procurement of the AN/ARC-21 Airborne Radio Transceivers," March 29, 1954.? The second was titled "Examination of the Pricing of the AN/ARC-21 Receiver-Transmitters," June 30, 1961.
The first investigation was about the Air Force procuring the ARC-21 before sufficient testing had been done on the prototype to verify performance.? The Air Force was in a panic with the build up of forces to fight the Korean War.? Congress was not critical of the problems facing the Air Force concerning the build up but they were concerned with the contracts let by the Air Force to RCA for an initial 3,900 sets and a follow on order for another 1,843 sets all before the delivery of the ARC-21 prototype for acceptance testing!??
The second investigation on pricing concerned the heat exchanger / pressure vessel which formed the outer case of the ARC-21.? This was the single costliest component of the ARC-21.? There was a $300 discrepancy between what RCA initially told the Air Force what it would cost and what RCA actually paid the contractor who made the heat exchanger.? Oh, well!
By the time of this first Congressional investigation, about 700 or so sets of the AN/ARC-21 had been delivered to the Air Force.? The problem with reliability was mainly due to vacuum tube and relay failures due to infant mortality and a lack of sufficient process control in the manufacturing of subminiature tubes and relays.? This is all well documented.? It should also be mentioned that there are approximately 100 relays used in the ARC-21.? The same number of relays are also used in the ARC-65.
There were also issues with other components such as resistors, capacitors and such but the main issue was with vacuum tubes and relays.? While the component manufacturers worked on improving their designs, overall reliability of the ARC-21 was improved with 100% component testing before module assembly.? This weeded out infant mortality failures of vacuum tubes and relays.? Completed ARC-21 sets then went through a 200 continuous hour operational test which included shake, rattle and roll while operating at elevated temperature.? Any failure found during the test returned the repaired ARC-21 to the beginning of the 200 hour test.? This forced the early failures and brought the reliability up to the point where the "Project Big Eva" testing program had verified that reliability was on par with other electronic systems used in the B-47.
With respect to your comments about the Navy choosing the ARC-38; perhaps you are not aware that the Navy had let a contract to Collins to develop the ARC-38 in 1952?? The Navy had also previously funded Collins for the development of the AN/ARC-26 AM transceiver.? ?The Navy issued this contract, worth a million dollars, in 1947.? It was cancelled when the prototype was evaluated in 1952.? The ARC-26 was the Navy's answer to the ARC-21 but evidently Collins had less luck with this design then RCA had had with the ARC-21.? The first Congressional investigation report also noted that Collins had commercialized much of the ARC-38, minus the SMO, in the form of the 618S-1.? What is common knowledge about the ARC-38 and the 618S-1 is not verified in the official record.
What caused the demise of the ARC-21 was the changeover from AM to SSB in the late 1950's and early 1960's.??As for the lack of reliability of the ARC-21 and the longevity of the ARC-65, it should be mentioned that they are practically the same radio.? Yes one is DSB and the other SSB but the change was accomplished without much of a redesign.? Both share better then 90% of the DNA of subminiature tubes and relays.? At least two modules are directly exchangeable between the two transceivers.? See the tube data below.? Bold type numbers are exclusive to that particular transceiver, all other tube types are also found in the other set.
ARC-21Type? ?? ?? ?Totals? ?? ?Description:0A2? ? ? ? ? ?1 ea ? ? ? ?150v VRT0B2? ? ? ? ? ?1 ea ? ? ? ?108v VRT2E26? ? ? ? ? 2 ea ? ? ? ?10Wattpentode3B22? ? ? ? ? 1 ea ? ? ? ?Full Waverectifier3B28? ? ? ? ? 4 ea ? ? ? ?HV diode4-65A? ? ? ? ? 4 ea ? ? ? ?65Watttetrode5636A ? ? ? ?16 ea ? ? ? ?Dual Cont pentode5643A ? ? ? ?1 ea ? ? ? ?thyratron5670? ? ? ? ? 1 ea ? ? ? ?Twin diode5687? ? ? ? ? 2 ea ? ? ? ?Double triode5718? ? ? ? ? 3 ea ? ? ? ?Medium MU triode5719A ? ? ? ?2 ea ? ? ? ?triode5840A ? ? ? ?14 ea ? ? ? ?Sharp Cutoffpentode5896A ? ? ? ?8 ea ? ? ? ?Twin diode5899A ? ? ? ?5 ea ? ? ? ?Semi-Remote pentode5902A ? ? ? ?3 ea ? ? ? ?Beam pentode6021A ? ? ? ?15 ea ? ? ? ?Twin triode991 ? ? ? ? ? ?1 ea? ? ? ? ? 58v VRTGrand total: 84 Tubes76 / 84 x 100 = 90.5% ofARC-21 tube types are also used in the ARC-65
ARC-65Type? ?? ?? ?? ?Totals? ?? ?Description:0B2? ? ? ? ? ? ?1 ea? ? ? ? ?108v VRT3B28? ? ? ? ? ? 4 ea ? ? ? ?HV diode4X250F ? ? ? ?2 ea ? ? ? ?PowerTetrode6CL6 ? ? ? ? ? ?2 ea ? ? ? ?Power Pentode5636S ? ? ? ?14 ea ? ? ? ?Dual Cont pentode5636AS ? ? ? ?2 ea ? ? ? ?Dual Cont pentode5643S? ? ? ? ? 1 ea ? ? ? ?thyratron5670WA? ? ? ?1 ea ? ? ? ?Twin diode5687? ? ? ? ? ? ? 2 ea ? ? ? ?Double triode5718S ? ? ? ? ? ?3 ea ? ? ? ?Medium MU triode5719S ? ? ? ? ? ?1 ea ? ? ? ?triode5840S ? ? ? ? ? ?19ea? ? ? Sharp Cutoff pentode5896A ? ? ? ? ? ?3 ea ? ? ? ?Twin diode5896S ? ? ? ? ? ?4 ea ? ? ? ?Twin diode5899AS? ? ? ? ? 6 ea ? ? ? ?Semi-Remotepentode5902AS? ? ? ? ? 2 ea ? ? ? ?Beam pentode6021A ? ? ? ? ? ?7 ea ? ? ? ?Twin triode6021S ? ? ? ? ? ?12 ea? ? ? ?Twin triode6021AS ? ? ? ? ? ?1 ea ? ? ? ?Twin triode991 ? ? ? ? ? ? ? ? ? ?1 ea ? ? ? ?58v VRTGrand total: 88 Tubes84 / 88 x 100 = 95.5% ofthe ARC-65 tube types are also used in the ARC-21
#yiv7963874434 -- filtered {}#yiv7963874434 filtered {}#yiv7963874434 filtered {}#yiv7963874434 p.yiv7963874434MsoNormal, #yiv7963874434 li.yiv7963874434MsoNormal, #yiv7963874434 div.yiv7963874434MsoNormal {margin:0in;font-size:11.0pt;font-family:sans-serif;}#yiv7963874434 span.yiv7963874434EmailStyle18 {font-family:sans-serif;color:windowtext;}#yiv7963874434 .yiv7963874434MsoChpDefault {font-size:10.0pt;}#yiv7963874434 filtered {}#yiv7963874434 div.yiv7963874434WordSection1 {}#yiv7963874434 ?The only difference beyond circuit changes for a balanced?modulator, a linear PA, a narrow bandwidth mechanical filter,?a product detector,?and a higher accuracy Reference Oscillator is the type number suffix of tubes used in both sets.? As an example, the RCA preliminary ARC-21 manual called for a JAN 5840, the ARC-21 military manual, which covered the improved ARC-21, called for a 5840A and the ARC-65 manual calls for a 5840S.? The only real difference between these three vacuum tubes is the level of testing done after the tube was manufactured.??Like Papa John says:? Better ingredients, better pizza!
Regards,Jim

 ?From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Mike Morrow
Sent: Thursday, October 29, 2020 6:59 AM
To: milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA ?It's interesting that the principle post-WWII aircraft HF-AM set selected by the USAF was the RT-128A/ARC-21 along with the R-224/ARR-36 aux receiver.? This RCA-made equipment had a very troubled history of of unreliability and extreme procurement costs that prompted U.S. Congressional investigation.? The extended delays for introduction of this equipment caused the WWII-vintage AN/ARC-8 (T-47A/ART-13 and BC-348-*) to be continued in service and for USAF purchases of many Collins 618S-1 sets to fill in for the missing AN/ARC-21. ?During the same period, the USN chose the Collins RT-311/ARC-38 and R-648/ARR-41 aux receiver to replace its AN/ARC-25 (T-47/ART-13 and R-105A/ARR-15).? From its introduction this Collins equipment was far more reliable and cost a small fraction of the USAF's RCA gear. ?When SSB became the desired mode, RCA developed a USB conversion of the RT-128A/ARC-21 into the RT-400/ARC-65.? It appears RCA saw a similar opportunity and developed the? USB conversion of the RT-311/ARC-38 into the RT-594/ARC-38A.? Although very complex, apparently the RT-594 was successful enough to remain flying for another decade and more.? Older USN aircraft with the AN/ARC-38A often retained it after an RT-648/ARC-94 (Collins 618T-2) was installed. ?It would be interesting to know if RCA used the same team to develop both the RT-400 and RT-594.? All things considered, I'd say they were very successful in military service.? ?Mike / KK5F
-----Original Message----- 
From: Ulrich N Fierz via Milsurplus 
Sent: Oct 29, 2020 3:53 AM 

Good morning Ray ?here I have a 618S-1 (no original control head) and a long time considered the ARC-38A, but I think I can easily confirm: the A is a nightmare...  ?Good luck with your many radios ?Ulrich? hb9aik - vk2ani ?Ulrich Fierz8044 Zurich/Switzerland

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201102/682586db/attachment-0001.html>

From frledda at att.net  Mon Nov  2 10:04:41 2020
From: frledda at att.net (frledda at att.net)
Date: Mon, 2 Nov 2020 09:04:41 -0600
Subject: [Milsurplus] Arc-38A as modified by RCA
In-Reply-To: <2113409776.795718.1604303013716@mail.yahoo.com>
References: <1258479195.379.1603969161058@wamui-abby.atl.sa.earthlink.net>	<06a101d6ae19$91e57dc0$b5b07940$@bellsouth.net>	<585093689.729142.1604260200512@mail.yahoo.com>	<914841023.751350.1604273182645@mail.yahoo.com>
	<2113409776.795718.1604303013716@mail.yahoo.com>
Message-ID: <03f301d6b129$7ed5e1d0$7c81a570$@att.net>

I don?t buy ?the better ingredients, better pizza? story.

 

Having been a design engineer at Collins and other companies, the need for screened components is a clear indication of a marginal design. I can only imagine the supply chain perturbations and cost associated with supplying the 5814S and other screened components.  

 

People may say that being the ARC-21 very complex (84 tubes and a large number of relays), this kind of instability and reliability is normal.  I beg to differ, based on my experience.  I was a system engineer for NATO on the Nike Hercules missile system, and the systems had thousands of tubes and relays, and never had to select components to make  it work.

 

Being the ARC-58 much more modern than the ARC-21/65, it is almost and unfair comparison, but it needs to be made.

 

ARC-65 vs ARC-58

Weight 245lb vs 175lbs

Volume 9.5ft^3 vs 5.85ft^3

Frequency range 2-24 MHz vs 2-29.999 MHz

Frequency Stability 150Hz @10MHz vs 10Hz @10MHz

Transmitter power  230W PEP SSB vs 900 MHz PEP SSB

MTBF 120h vs 290h

 

The Univac antenna coupler was a good coupler but inferior in reliability to the 180R-6, due to the integration of the servo amps into the coupler itself. The servo amps used magamps that suffered from temperature extremes, Collins?s choice to keep the controller in the pressurized vessel was key for their better reliability.  Also, the Collins 180R-6 used a low pass filter architecture that further reduced higher harmonics. The Univac used high pass filter architecture. 

 

Best, Francesco K5URG

 

 

 

From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Jim Whartenby via Milsurplus
Sent: Monday, November 2, 2020 1:44 AM
To: 
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

Mike

I do not agree with you that the ARC-21 had a history of unreliability.  It certainly was not much different then any other system found in the B-47 bomber other then the K Bombing and Navigation System.  This system weighed in at over a thousand pounds and used 370 vacuum tubes and an even higher number of relays.  MTBF for the BNS was so low that spare modules were carried in the B-47 Navigator's compartment.

 

It is rarely mentioned that the AN/ARC-21 was designed for use in the B-47 where it was mounted in the rear of the aircraft, aft of the rear landing gear, along with the ARC-27 UHF transceiver.  This location is where vibration and temperature extremes work it's magic.  Any HF transceivers used in place of the ARC-21 were installed in support aircraft such as the KC-97 or KC-135, not in a B-47.  No other HF transceiver available at this time was able to operate under the extreme conditions found in the B-47.  

 

The ARC-21 did have initial teething problems not unlike many other "state of the art" systems found in the B-47 or other aircraft.  But these problems were addressed and corrected as the source of the problems were determined and the failure mechanisms understood.  This was verified in the final report of "Project Big Eva" An Accelerated Service Test of Radio Set AN/ARC-21 in March, 1955.

 

There were two U.S. Congressional investigations concerning the ARC-21 of which I am aware.  The first was titled "Air Force Development and Procurement of the AN/ARC-21 Airborne Radio Transceivers," March 29, 1954.  The second was titled "Examination of the Pricing of the AN/ARC-21 Receiver-Transmitters," June 30, 1961.

 

The first investigation was about the Air Force procuring the ARC-21 before sufficient testing had been done on the prototype to verify performance.  The Air Force was in a panic with the build up of forces to fight the Korean War.  Congress was not critical of the problems facing the Air Force concerning the build up but they were concerned with the contracts let by the Air Force to RCA for an initial 3,900 sets and a follow on order for another 1,843 sets all before the delivery of the ARC-21 prototype for acceptance testing!  

 

The second investigation on pricing concerned the heat exchanger / pressure vessel which formed the outer case of the ARC-21.  This was the single costliest component of the ARC-21.  There was a $300 discrepancy between what RCA initially told the Air Force what it would cost and what RCA actually paid the contractor who made the heat exchanger.  Oh, well!

 

By the time of this first Congressional investigation, about 700 or so sets of the AN/ARC-21 had been delivered to the Air Force.  The problem with reliability was mainly due to vacuum tube and relay failures due to infant mortality and a lack of sufficient process control in the manufacturing of subminiature tubes and relays.  This is all well documented.  It should also be mentioned that there are approximately 100 relays used in the ARC-21.  The same number of relays are also used in the ARC-65.

 

There were also issues with other components such as resistors, capacitors and such but the main issue was with vacuum tubes and relays.  While the component manufacturers worked on improving their designs, overall reliability of the ARC-21 was improved with 100% component testing before module assembly.  This weeded out infant mortality failures of vacuum tubes and relays.  Completed ARC-21 sets then went through a 200 continuous hour operational test which included shake, rattle and roll while operating at elevated temperature.  Any failure found during the test returned the repaired ARC-21 to the beginning of the 200 hour test.  This forced the early failures and brought the reliability up to the point where the "Project Big Eva" testing program had verified that reliability was on par with other electronic systems used in the B-47.

 

With respect to your comments about the Navy choosing the ARC-38; perhaps you are not aware that the Navy had let a contract to Collins to develop the ARC-38 in 1952?  The Navy had also previously funded Collins for the development of the AN/ARC-26 AM transceiver.   The Navy issued this contract, worth a million dollars, in 1947.  It was cancelled when the prototype was evaluated in 1952.  The ARC-26 was the Navy's answer to the ARC-21 but evidently Collins had less luck with this design then RCA had had with the ARC-21.  The first Congressional investigation report also noted that Collins had commercialized much of the ARC-38, minus the SMO, in the form of the 618S-1.  What is common knowledge about the ARC-38 and the 618S-1 is not verified in the official record.

 

What caused the demise of the ARC-21 was the changeover from AM to SSB in the late 1950's and early 1960's.  As for the lack of reliability of the ARC-21 and the longevity of the ARC-65, it should be mentioned that they are practically the same radio.  Yes one is DSB and the other SSB but the change was accomplished without much of a redesign.  Both share better then 90% of the DNA of subminiature tubes and relays.  At least two modules are directly exchangeable between the two transceivers.  See the tube data below.  Bold type numbers are exclusive to that particular transceiver, all other tube types are also found in the other set.

 

ARC-21

Type         Totals      Description:

0A2           1 ea        150v VRT

0B2           1 ea        108v VRT

2E26          2 ea        10Watt pentode

3B22          1 ea        Full Wave rectifier

3B28          4 ea        HV diode

4-65A          4 ea        65Watt tetrode

5636A        16 ea        Dual Cont pentode

5643A        1 ea        thyratron

5670          1 ea        Twin diode

5687          2 ea        Double triode

5718          3 ea        Medium MU triode

5719A        2 ea        triode

5840A        14 ea        Sharp Cutoff pentode

5896A        8 ea        Twin diode

5899A        5 ea        Semi-Remote pentode

5902A        3 ea        Beam pentode

6021A        15 ea        Twin triode

991            1 ea          58v VRT

Grand total: 84 Tubes

76 / 84 x 100 = 90.5% of ARC-21 tube types are also used in the ARC-65

 

ARC-65

Type            Totals      Description:

0B2             1 ea         108v VRT

3B28            4 ea        HV diode

4X250F        2 ea        Power Tetrode

6CL6            2 ea        Power Pentode

5636S        14 ea        Dual Cont pentode

5636AS        2 ea        Dual Cont pentode

5643S          1 ea        thyratron

5670WA       1 ea        Twin diode

5687              2 ea        Double triode

5718S            3 ea        Medium MU triode

5719S            1 ea        triode

5840S            19 ea      Sharp Cutoff pentode

5896A            3 ea        Twin diode

5896S            4 ea        Twin diode

5899AS          6 ea        Semi-Remote pentode

5902AS          2 ea        Beam pentode

6021A            7 ea        Twin triode

6021S            12 ea       Twin triode

6021AS            1 ea        Twin triode

991                    1 ea        58v VRT

Grand total: 88 Tubes

84 / 88 x 100 = 95.5% of the ARC-65 tube types are also used in the ARC-21

 

 The only difference beyond circuit changes for a balanced modulator, a linear PA, a narrow bandwidth mechanical filter, a product detector, and a higher accuracy Reference Oscillator is the type number suffix of tubes used in both sets.  As an example, the RCA preliminary ARC-21 manual called for a JAN 5840, the ARC-21 military manual, which covered the improved ARC-21, called for a 5840A and the ARC-65 manual calls for a 5840S.  The only real difference between these three vacuum tubes is the level of testing done after the tube was manufactured.  Like Papa John says:  Better ingredients, better pizza!

 

Regards,

Jim

 

 

 

From: milsurplus-bounces at mailman.qth.net <mailto:milsurplus-bounces at mailman.qth.net>  <milsurplus-bounces at mailman.qth.net <mailto:milsurplus-bounces at mailman.qth.net> > On Behalf Of Mike Morrow
Sent: Thursday, October 29, 2020 6:59 AM
To: milsurplus at mailman.qth.net <mailto:milsurplus at mailman.qth.net> 
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

It's interesting that the principle post-WWII aircraft HF-AM set selected by the USAF was the RT-128A/ARC-21 along with the R-224/ARR-36 aux receiver.  This RCA-made equipment had a very troubled history of of unreliability and extreme procurement costs that prompted U.S. Congressional investigation.  The extended delays for introduction of this equipment caused the WWII-vintage AN/ARC-8 (T-47A/ART-13 and BC-348-*) to be continued in service and for USAF purchases of many Collins 618S-1 sets to fill in for the missing AN/ARC-21.

 

During the same period, the USN chose the Collins RT-311/ARC-38 and R-648/ARR-41 aux receiver to replace its AN/ARC-25 (T-47/ART-13 and R-105A/ARR-15).  From its introduction this Collins equipment was far more reliable and cost a small fraction of the USAF's RCA gear.

 

When SSB became the desired mode, RCA developed a USB conversion of the RT-128A/ARC-21 into the RT-400/ARC-65.  It appears RCA saw a similar opportunity and developed the  USB conversion of the RT-311/ARC-38 into the RT-594/ARC-38A.  Although very complex, apparently the RT-594 was successful enough to remain flying for another decade and more.  Older USN aircraft with the AN/ARC-38A often retained it after an RT-648/ARC-94 (Collins 618T-2) was installed.

 

It would be interesting to know if RCA used the same team to develop both the RT-400 and RT-594.  All things considered, I'd say they were very successful in military service. 

 

Mike / KK5F

-----Original Message----- 
From: Ulrich N Fierz via Milsurplus 
Sent: Oct 29, 2020 3:53 AM 

Good morning Ray

 

here I have a 618S-1 (no original control head) and a long time considered the ARC-38A, but I think I can easily confirm: the A is a nightmare... 

 

Good luck with your many radios

 

Ulrich  hb9aik - vk2ani

 

Ulrich Fierz

8044 Zurich/Switzerland

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201102/a94d451f/attachment-0001.html>

From old_radio at aol.com  Mon Nov  2 14:15:21 2020
From: old_radio at aol.com (Jim Whartenby)
Date: Mon, 2 Nov 2020 19:15:21 +0000 (UTC)
Subject: [Milsurplus] Arc-38A as modified by RCA
In-Reply-To: <03f301d6b129$7ed5e1d0$7c81a570$@att.net>
References: <1258479195.379.1603969161058@wamui-abby.atl.sa.earthlink.net>
	<06a101d6ae19$91e57dc0$b5b07940$@bellsouth.net>
	<585093689.729142.1604260200512@mail.yahoo.com>
	<914841023.751350.1604273182645@mail.yahoo.com>
	<2113409776.795718.1604303013716@mail.yahoo.com>
	<03f301d6b129$7ed5e1d0$7c81a570$@att.net>
Message-ID: <1187432402.907742.1604344521641@mail.yahoo.com>

Francesco
The pizza remark was done "tong in cheek" but it does indicate that better components makes for a better product which was what I was aiming for.
"...the need for screened components is a clear indication of a marginal design."
Don't know what to make of this.? Clearly, a 5654W is not the same as a 6AK5 even though they may preform the same in most circuits.? If the specification calls for a 5654W then one has automatically screened that component.? It has already gone through the various tests that have weeded out inferior examples.??In the early 1950's, these types of component specifications did not exist.? Commercial as opposed to?JAN components were all that were then available.??
The experience in addressing the shortfalls in the ARC-21 program, among many other programs of that time period, led to the research into failure analysis and the creation of various component specifications needed to increase the quality of components and by extension, the reliability of the electronics system.? Clearly, the ARC-21 met all design specifications in the original contract; the totalbuild as of 20 April 1961 was 5,394 sets.? The issue was that when the system was first installed in the harsh B-47 environment, the life expectancy fell short.? Those issues that caused the low reliability were addressed and corrected.
In today's?world, almost all of the high-rel component specifications have been rescinded because commercial components now are of vastly?higher quality then those made in the 1950's.? That is one of the many pitfalls in looking back 70 odd years from the perspective of the year 2020.? The products made back then fall short of today's expectations but at the time, they were marvelous.
"...it is almost and (sic) unfair comparison, but it needs to be made".
If it is an unfair comparison, why not compare the ARC-21 with it's contemporaries?
.? ?? ?? ?? ?? ?? ?? ?? ?? ?ARC-21? ?? ???? ??618S? ?? ?? ??ARC-38Freqrange:? ??? ?? ?2-24 mc? ?? ?? ?2-25 mc? ?? ? ?2-25 mcChannels:? ?? ??? ?? ?44,000? ?? ??? ?144? ?? ?? ?? ?? ? 35,250Ch.spacing:? ?? ?? ?500 cycles? ?? ?NA? ?? ?? ?? ?? ?500 / 1000* cyclesFreq.Stability:? ?? ?0.0015%? ?? ?0.007%? ?? ?? ??0.01%Altitude:? ?? ?? ?? ?? ?50kfeet? ?? ?? ?50k feet? ?? ?? ?50k feet? (See Note below)Op.temp:? ?? ?? ?? ??-55C/+85C? ?? ?Unk? ?? ?? ?? ?? ?UnkRFpower:? ?? ?? ?? ??>100 watts? ?? ?>90 watts*? ?>90 watts*freqsetup:? ?? ?? ?? ??direct input? ?? ?crystal? ?? ?? ??code bookWeight**?? ?? ?? ?? ??136 lbs? ?? ?? ?? ??64 lbs? ?? ?? ??73 lbs.*Frequencydependent, high frequency spec shown**R/T+ mount, approximately half of the ARC-21 mount is part of the R/TunitNote:? The618S or ARC-38 operating at 50,000 feet seems a bit optimistic to me. Air pressure is down to about 11.5% that of sea level. How is theR/T unit cooled at this altitude? Neither the R/T unit nor themounting rack have fans to move air. What about condensation ofwater on the modules as the aircraft climbs to operational altitudefrom a hot and humid airfield?
The issue really is that being the first to do something is much, much harder then when you can benefit?from the mistakes made by those who came before you.? It is so much easier to play catch-up then to weed through all of the possibilities to find the path to a successful design.? Many times it is not possible to get to do a "do-over."? I am quite sure that the RCA designers would have preferred a second chance at the ARC-21 design.? There is always room for improvement, isn't there?
Regards,Jim

I wonder why people argue over the 10% of their differences and ignore the 90% they agree on?

-----Original Message-----
From: frledda at att.net
To: milsurplus at mailman.qth.net
Sent: Mon, Nov 2, 2020 9:04 am
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

#yiv2449388775 #yiv2449388775 -- _filtered {} _filtered {} _filtered {}#yiv2449388775 #yiv2449388775 p.yiv2449388775MsoNormal, #yiv2449388775 li.yiv2449388775MsoNormal, #yiv2449388775 div.yiv2449388775MsoNormal {margin:0in;font-size:11.0pt;font-family:sans-serif;}#yiv2449388775 a:link, #yiv2449388775 span.yiv2449388775MsoHyperlink {color:#0563C1;text-decoration:underline;}#yiv2449388775 span.yiv2449388775EmailStyle27 {font-family:sans-serif;color:windowtext;}#yiv2449388775 .yiv2449388775MsoChpDefault {font-family:sans-serif;} _filtered {}#yiv2449388775 div.yiv2449388775WordSection1 {}#yiv2449388775 I don?t buy ?the better ingredients, better pizza? story. ?Having been a design engineer at Collins and other companies, the need for screened components is a clear indication of a marginal design. I can only imagine the supply chain perturbations and cost associated with supplying the 5814S and other screened components.?  ?People may say that being the ARC-21 very complex (84 tubes and a large number of relays), this kind of instability and reliability is normal.? I beg to differ, based on my experience.? I was a system engineer for NATO on the Nike Hercules missile system, and the systems had thousands of tubes and relays, and never had to select components to make? it work. ?Being the ARC-58 much more modern than the ARC-21/65, it is almost and unfair comparison, but it needs to be made. ?ARC-65 vs ARC-58Weight 245lb vs 175lbsVolume 9.5ft^3 vs 5.85ft^3Frequency range 2-24 MHz vs 2-29.999 MHzFrequency Stability 150Hz @10MHz vs 10Hz @10MHzTransmitter power? 230W PEP SSB vs 900 MHz PEP SSBMTBF 120h vs 290h ?The Univac antenna coupler was a good coupler but inferior in reliability to the 180R-6, due to the integration of the servo amps into the coupler itself. The servo amps used magamps that suffered from temperature extremes, Collins?s choice to keep the controller in the pressurized vessel was key for their better reliability. ?Also, the Collins 180R-6 used a low pass filter architecture that further reduced higher harmonics. The Univac used high pass filter architecture.  ?Best, Francesco K5URG ? ? ?From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Jim Whartenby via Milsurplus
Sent: Monday, November 2, 2020 1:44 AM
To: 
Subject: Re: [Milsurplus] Arc-38A as modified by RCA ?MikeI do not agree with you that the ARC-21 had a history of unreliability.? It certainly was not much different then any other system found in the B-47 bomber other then the K Bombing and Navigation System.? This system weighed in at over a thousand pounds and used 370 vacuum tubes and an even higher number of relays.? MTBF for the BNS was so low that spare modules were carried in the B-47 Navigator's compartment. ?It is rarely mentioned that the AN/ARC-21 was designed for use in the B-47 where it was mounted in the rear of the aircraft, aft of the rear landing gear, along with the ARC-27 UHF transceiver.? This location is where vibration and temperature extremes work it's magic.? Any HF transceivers used in place of the ARC-21 were installed in support aircraft such as the KC-97 or KC-135, not in a B-47.? No other HF transceiver available at this time was able to operate under the extreme conditions found in the B-47.?? ?The ARC-21 did have initial teething problems not unlike many other "state of the art" systems found in the B-47 or other aircraft.? But these problems were addressed and corrected as the source of the problems were determined and the failure mechanisms understood.? This was verified in the final report of "Project Big Eva" An Accelerated Service Test of Radio Set AN/ARC-21 in March, 1955. ?There were two U.S. Congressional investigations concerning the ARC-21 of which I am aware.? The first was titled "Air Force Development and Procurement of the AN/ARC-21 Airborne Radio Transceivers," March 29, 1954.? The second was titled "Examination of the Pricing of the AN/ARC-21 Receiver-Transmitters," June 30, 1961. ?The first investigation was about the Air Force procuring the ARC-21 before sufficient testing had been done on the prototype to verify performance.? The Air Force was in a panic with the build up of forces to fight the Korean War.? Congress was not critical of the problems facing the Air Force concerning the build up but they were concerned with the contracts let by the Air Force to RCA for an initial 3,900 sets and a follow on order for another 1,843 sets all before the delivery of the ARC-21 prototype for acceptance testing!?? ?The second investigation on pricing concerned the heat exchanger / pressure vessel which formed the outer case of the ARC-21.? This was the single costliest component of the ARC-21.? There was a $300 discrepancy between what RCA initially told the Air Force what it would cost and what RCA actually paid the contractor who made the heat exchanger.? Oh, well! ?By the time of this first Congressional investigation, about 700 or so sets of the AN/ARC-21 had been delivered to the Air Force.? The problem with reliability was mainly due to vacuum tube and relay failures due to infant mortality and a lack of sufficient process control in the manufacturing of subminiature tubes and relays.? This is all well documented.? It should also be mentioned that there are approximately 100 relays used in the ARC-21.? The same number of relays are also used in the ARC-65. ?There were also issues with other components such as resistors, capacitors and such but the main issue was with vacuum tubes and relays.? While the component manufacturers worked on improving their designs, overall reliability of the ARC-21 was improved with 100% component testing before module assembly.? This weeded out infant mortality failures of vacuum tubes and relays.? Completed ARC-21 sets then went through a 200 continuous hour operational test which included shake, rattle and roll while operating at elevated temperature.? Any failure found during the test returned the repaired ARC-21 to the beginning of the 200 hour test.? This forced the early failures and brought the reliability up to the point where the "Project Big Eva" testing program had verified that reliability was on par with other electronic systems used in the B-47. ?With respect to your comments about the Navy choosing the ARC-38; perhaps you are not aware that the Navy had let a contract to Collins to develop the ARC-38 in 1952?? The Navy had also previously funded Collins for the development of the AN/ARC-26 AM transceiver.? ?The Navy issued this contract, worth a million dollars, in 1947.? It was cancelled when the prototype was evaluated in 1952.? The ARC-26 was the Navy's answer to the ARC-21 but evidently Collins had less luck with this design then RCA had had with the ARC-21.? The first Congressional investigation report also noted that Collins had commercialized much of the ARC-38, minus the SMO, in the form of the 618S-1.? What is common knowledge about the ARC-38 and the 618S-1 is not verified in the official record. ?What caused the demise of the ARC-21 was the changeover from AM to SSB in the late 1950's and early 1960's.??As for the lack of reliability of the ARC-21 and the longevity of the ARC-65, it should be mentioned that they are practically the same radio.? Yes one is DSB and the other SSB but the change was accomplished without much of a redesign.? Both share better then 90% of the DNA of subminiature tubes and relays.? At least two modules are directly exchangeable between the two transceivers.? See the tube data below.? Bold type numbers are exclusive to that particular transceiver, all other tube types are also found in the other set. ?ARC-21Type? ?? ?? ?Totals? ?? ?Description:0A2? ? ? ? ? ?1 ea ? ? ? ?150v VRT0B2? ? ? ? ? ?1 ea ? ? ? ?108v VRT2E26? ? ? ? ? 2 ea ? ? ? ?10Watt pentode3B22? ? ? ? ? 1 ea ? ? ? ?Full Wave rectifier3B28? ? ? ? ? 4 ea ? ? ? ?HV diode4-65A? ? ? ? ? 4 ea ? ? ? ?65Watt tetrode5636A ? ? ? ?16 ea ? ? ? ?Dual Cont pentode5643A ? ? ? ?1 ea ? ? ? ?thyratron5670? ? ? ? ? 1 ea ? ? ? ?Twin diode5687? ? ? ? ? 2 ea ? ? ? ?Double triode5718? ? ? ? ? 3 ea ? ? ? ?Medium MU triode5719A ? ? ? ?2 ea ? ? ? ?triode5840A ? ? ? ?14 ea ? ? ? ?Sharp Cutoff pentode5896A ? ? ? ?8 ea ? ? ? ?Twin diode5899A ? ? ? ?5 ea ? ? ? ?Semi-Remote pentode5902A ? ? ? ?3 ea ? ? ? ?Beam pentode6021A ? ? ? ?15 ea ? ? ? ?Twin triode991 ? ? ? ? ? ?1 ea? ? ? ? ? 58v VRTGrand total: 84 Tubes76 / 84 x 100 = 90.5% of ARC-21 tube types are also used in the ARC-65 ?ARC-65Type? ?? ?? ?? ?Totals? ?? ?Description:0B2? ? ? ? ? ? ?1 ea? ? ? ? ?108v VRT3B28? ? ? ? ? ? 4 ea ? ? ? ?HV diode4X250F ? ? ? ?2 ea ? ? ? ?Power Tetrode6CL6 ? ? ? ? ? ?2 ea ? ? ? ?Power Pentode5636S ? ? ? ?14 ea ? ? ? ?Dual Cont pentode5636AS ? ? ? ?2 ea ? ? ? ?Dual Cont pentode5643S? ? ? ? ? 1 ea ? ? ? ?thyratron5670WA? ? ? ?1 ea ? ? ? ?Twin diode5687? ? ? ? ? ? ? 2 ea ? ? ? ?Double triode5718S ? ? ? ? ? ?3 ea ? ? ? ?Medium MU triode5719S ? ? ? ? ? ?1 ea ? ? ? ?triode5840S ? ? ? ? ? ?19 ea? ? ? Sharp Cutoff pentode5896A ? ? ? ? ? ?3 ea ? ? ? ?Twin diode5896S ? ? ? ? ? ?4 ea ? ? ? ?Twin diode5899AS? ? ? ? ? 6 ea ? ? ? ?Semi-Remote pentode5902AS? ? ? ? ? 2 ea ? ? ? ?Beam pentode6021A ? ? ? ? ? ?7 ea ? ? ? ?Twin triode6021S ? ? ? ? ? ?12 ea? ? ? ?Twin triode6021AS ? ? ? ? ? ?1 ea ? ? ? ?Twin triode991 ? ? ? ? ? ? ? ? ? ?1 ea ? ? ? ?58v VRTGrand total: 88 Tubes84 / 88 x 100 = 95.5% of the ARC-65 tube types are also used in the ARC-21 ??The only difference beyond circuit changes for a balanced?modulator, a linear PA, a narrow bandwidth mechanical filter,?a product detector,?and a higher accuracy Reference Oscillator is the type number suffix of tubes used in both sets.? As an example, the RCA preliminary ARC-21 manual called for a JAN 5840, the ARC-21 military manual, which covered the improved ARC-21, called for a 5840A and the ARC-65 manual calls for a 5840S.? The only real difference between these three vacuum tubes is the level of testing done after the tube was manufactured.??Like Papa John says:? Better ingredients, better pizza! ?Regards,Jim ? ??From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Mike Morrow
Sent: Thursday, October 29, 2020 6:59 AM
To: milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA?It's interesting that the principle post-WWII aircraft HF-AM set selected by the USAF was the RT-128A/ARC-21 along with the R-224/ARR-36 aux receiver.? This RCA-made equipment had a very troubled history of of unreliability and extreme procurement costs that prompted U.S. Congressional investigation.? The extended delays for introduction of this equipment caused the WWII-vintage AN/ARC-8 (T-47A/ART-13 and BC-348-*) to be continued in service and for USAF purchases of many Collins 618S-1 sets to fill in for the missing AN/ARC-21.?During the same period, the USN chose the Collins RT-311/ARC-38 and R-648/ARR-41 aux receiver to replace its AN/ARC-25 (T-47/ART-13 and R-105A/ARR-15).? From its introduction this Collins equipment was far more reliable and cost a small fraction of the USAF's RCA gear.?When SSB became the desired mode, RCA developed a USB conversion of the RT-128A/ARC-21 into the RT-400/ARC-65.? It appears RCA saw a similar opportunity and developed the? USB conversion of the RT-311/ARC-38 into the RT-594/ARC-38A.? Although very complex, apparently the RT-594 was successful enough to remain flying for another decade and more.? Older USN aircraft with the AN/ARC-38A often retained it after an RT-648/ARC-94 (Collins 618T-2) was installed.?It would be interesting to know if RCA used the same team to develop both the RT-400 and RT-594.? All things considered, I'd say they were very successful in military service.??Mike / KK5F
-----Original Message----- 
From: Ulrich N Fierz via Milsurplus 
Sent: Oct 29, 2020 3:53 AM Good morning Ray?here I have a 618S-1 (no original control head) and a long time considered the ARC-38A, but I think I can easily confirm: the A is a nightmare... ?Good luck with your many radios?Ulrich? hb9aik - vk2ani?Ulrich Fierz8044 Zurich/Switzerland
______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201102/c24fc527/attachment-0001.html>

From frledda at att.net  Mon Nov  2 15:27:31 2020
From: frledda at att.net (frledda at att.net)
Date: Mon, 2 Nov 2020 14:27:31 -0600
Subject: [Milsurplus] Arc-38A as modified by RCA
In-Reply-To: <1187432402.907742.1604344521641@mail.yahoo.com>
References: <1258479195.379.1603969161058@wamui-abby.atl.sa.earthlink.net>	<06a101d6ae19$91e57dc0$b5b07940$@bellsouth.net>	<585093689.729142.1604260200512@mail.yahoo.com>	<914841023.751350.1604273182645@mail.yahoo.com>	<2113409776.795718.1604303013716@mail.yahoo.com>	<03f301d6b129$7ed5e1d0$7c81a570$@att.net>
	<1187432402.907742.1604344521641@mail.yahoo.com>
Message-ID: <052501d6b156$97f70360$c7e50a20$@att.net>

Jim,

 

On this particular topic, we will agree to disagree.  

 

There is a difference between reliability of a component and its spec variance.  I believe that the ARC-21/65 needed ?some selected components? and the 5814S is the proof.

 

The ARC-38 did not suffer from this, as any garden variety component worked in it. When I worked at Collins, we tested new designs with components form different production batches and suppliers to make evaluate the design stability. Critical circuits were validated by exercising the possible variances of each components.  We temp tested and exceeded the temp/voltage ranges by 30%. If it did not work, we were going back to drawing board.

 

As a design manager and later design executive, my approach was to force my designers to use the standard supply chain components, and only in special cases, I allowed to use selected components.  A selected component costs multiple times as much as a standard production one, and creates supply chain issues (new PN, new procurement, more cost, more inventory, more taxes and unhappy customers). 

 

Already in the 70s, designers at Collins (HP and others) designers were discouraged from designing products with tuning/adjustments like pots (etc.), as they required extra manufacturing time. This approach required better quality designs.

 

I think that my feelings about the ARC-21/65 are not very positive, as I think that this product was half-baked when it entered production.  Later efforts improved the product.

 

Again, I enjoyed this conversation, but forgive me for disagreeing with you ?

 

Best, Francesco

 

 

 

 

 

From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Jim Whartenby via Milsurplus
Sent: Monday, November 2, 2020 1:15 PM
To: milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

Francesco

 

The pizza remark was done "tong in cheek" but it does indicate that better components makes for a better product which was what I was aiming for.

 

"...the need for screened components is a clear indication of a marginal design."

Don't know what to make of this.  Clearly, a 5654W is not the same as a 6AK5 even though they may preform the same in most circuits.  If the specification calls for a 5654W then one has automatically screened that component.  It has already gone through the various tests that have weeded out inferior examples.  In the early 1950's, these types of component specifications did not exist.  Commercial as opposed to JAN components were all that were then available.  

 

The experience in addressing the shortfalls in the ARC-21 program, among many other programs of that time period, led to the research into failure analysis and the creation of various component specifications needed to increase the quality of components and by extension, the reliability of the electronics system.  Clearly, the ARC-21 met all design specifications in the original contract; the total build as of 20 April 1961 was 5,394 sets.  The issue was that when the system was first installed in the harsh B-47 environment, the life expectancy fell short.  Those issues that caused the low reliability were addressed and corrected.

 

In today's world, almost all of the high-rel component specifications have been rescinded because commercial components now are of vastly higher quality then those made in the 1950's.  That is one of the many pitfalls in looking back 70 odd years from the perspective of the year 2020.  The products made back then fall short of today's expectations but at the time, they were marvelous.

 

"...it is almost and (sic) unfair comparison, but it needs to be made".

If it is an unfair comparison, why not compare the ARC-21 with it's contemporaries?

 

.                           ARC-21            618S          ARC-38

Freq range:          2-24 mc         2-25 mc        2-25 mc

Channels:             44,000          144                35,250

Ch. spacing:         500 cycles      NA               500 / 1000* cycles

Freq. Stability:      0.0015%      0.007%          0.01%

Altitude:               50k feet         50k feet         50k feet  (See Note below)

Op. temp:             -55C/+85C      Unk               Unk

RF power:             >100 watts      >90 watts*   >90 watts*

freq setup:             direct input      crystal          code book

Weight**              136 lbs             64 lbs          73 lbs.

*Frequency dependent, high frequency spec shown

**R/T + mount, approximately half of the ARC-21 mount is part of the R/T unit

Note:  The 618S or ARC-38 operating at 50,000 feet seems a bit optimistic to me. Air pressure is down to about 11.5% that of sea level. How is the R/T unit cooled at this altitude? Neither the R/T unit nor the mounting rack have fans to move air. What about condensation of water on the modules as the aircraft climbs to operational altitude from a hot and humid airfield?

 

The issue really is that being the first to do something is much, much harder then when you can benefit from the mistakes made by those who came before you.  It is so much easier to play catch-up then to weed through all of the possibilities to find the path to a successful design.  Many times it is not possible to get to do a "do-over."  I am quite sure that the RCA designers would have preferred a second chance at the ARC-21 design.  There is always room for improvement, isn't there?

 

Regards,

Jim

 

I wonder why people argue over the 10% of their differences and ignore the 90% they agree on?

 

-----Original Message-----
From: frledda at att.net <mailto:frledda at att.net> 
To: milsurplus at mailman.qth.net <mailto:milsurplus at mailman.qth.net> 
Sent: Mon, Nov 2, 2020 9:04 am
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

I don?t buy ?the better ingredients, better pizza? story.

 

Having been a design engineer at Collins and other companies, the need for screened components is a clear indication of a marginal design. I can only imagine the supply chain perturbations and cost associated with supplying the 5814S and other screened components.  

 

People may say that being the ARC-21 very complex (84 tubes and a large number of relays), this kind of instability and reliability is normal.  I beg to differ, based on my experience.  I was a system engineer for NATO on the Nike Hercules missile system, and the systems had thousands of tubes and relays, and never had to select components to make  it work.

 

Being the ARC-58 much more modern than the ARC-21/65, it is almost and unfair comparison, but it needs to be made.

 

ARC-65 vs ARC-58

Weight 245lb vs 175lbs

Volume 9.5ft^3 vs 5.85ft^3

Frequency range 2-24 MHz vs 2-29.999 MHz

Frequency Stability 150Hz @10MHz vs 10Hz @10MHz

Transmitter power  230W PEP SSB vs 900 MHz PEP SSB

MTBF 120h vs 290h

 

The Univac antenna coupler was a good coupler but inferior in reliability to the 180R-6, due to the integration of the servo amps into the coupler itself. The servo amps used magamps that suffered from temperature extremes, Collins?s choice to keep the controller in the pressurized vessel was key for their better reliability.  Also, the Collins 180R-6 used a low pass filter architecture that further reduced higher harmonics. The Univac used high pass filter architecture 

 

Best, Francesco K5URG

 

 

 

From: milsurplus-bounces at mailman.qth.net <mailto:milsurplus-bounces at mailman.qth.net>  <milsurplus-bounces at mailman.qth.net <mailto:milsurplus-bounces at mailman.qth.net> > On Behalf Of Jim Whartenby via Milsurplus
Sent: Monday, November 2, 2020 1:44 AM
To: 
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

Mike

I do not agree with you that the ARC-21 had a history of unreliability.  It certainly was not much different then any other system found in the B-47 bomber other then the K Bombing and Navigation System.  This system weighed in at over a thousand pounds and used 370 vacuum tubes and an even higher number of relays.  MTBF for the BNS was so low that spare modules were carried in the B-47 Navigator's compartment.

 

It is rarely mentioned that the AN/ARC-21 was designed for use in the B-47 where it was mounted in the rear of the aircraft, aft of the rear landing gear, along with the ARC-27 UHF transceiver.  This location is where vibration and temperature extremes work it's magic.  Any HF transceivers used in place of the ARC-21 were installed in support aircraft such as the KC-97 or KC-135, not in a B-47.  No other HF transceiver available at this time was able to operate under the extreme conditions found in the B-47.  

 

The ARC-21 did have initial teething problems not unlike many other "state of the art" systems found in the B-47 or other aircraft.  But these problems were addressed and corrected as the source of the problems were determined and the failure mechanisms understood.  This was verified in the final report of "Project Big Eva" An Accelerated Service Test of Radio Set AN/ARC-21 in March, 1955.

 

There were two U.S. Congressional investigations concerning the ARC-21 of which I am aware.  The first was titled "Air Force Development and Procurement of the AN/ARC-21 Airborne Radio Transceivers," March 29, 1954.  The second was titled "Examination of the Pricing of the AN/ARC-21 Receiver-Transmitters," June 30, 1961.

 

The first investigation was about the Air Force procuring the ARC-21 before sufficient testing had been done on the prototype to verify performance.  The Air Force was in a panic with the build up of forces to fight the Korean War.  Congress was not critical of the problems facing the Air Force concerning the build up but they were concerned with the contracts let by the Air Force to RCA for an initial 3,900 sets and a follow on order for another 1,843 sets all before the delivery of the ARC-21 prototype for acceptance testing!  

 

The second investigation on pricing concerned the heat exchanger / pressure vessel which formed the outer case of the ARC-21.  This was the single costliest component of the ARC-21.  There was a $300 discrepancy between what RCA initially told the Air Force what it would cost and what RCA actually paid the contractor who made the heat exchanger.  Oh, well!

 

By the time of this first Congressional investigation, about 700 or so sets of the AN/ARC-21 had been delivered to the Air Force.  The problem with reliability was mainly due to vacuum tube and relay failures due to infant mortality and a lack of sufficient process control in the manufacturing of subminiature tubes and relays.  This is all well documented.  It should also be mentioned that there are approximately 100 relays used in the ARC-21.  The same number of relays are also used in the ARC-65.

 

There were also issues with other components such as resistors, capacitors and such but the main issue was with vacuum tubes and relays.  While the component manufacturers worked on improving their designs, overall reliability of the ARC-21 was improved with 100% component testing before module assembly.  This weeded out infant mortality failures of vacuum tubes and relays.  Completed ARC-21 sets then went through a 200 continuous hour operational test which included shake, rattle and roll while operating at elevated temperature.  Any failure found during the test returned the repaired ARC-21 to the beginning of the 200 hour test.  This forced the early failures and brought the reliability up to the point where the "Project Big Eva" testing program had verified that reliability was on par with other electronic systems used in the B-47.

 

With respect to your comments about the Navy choosing the ARC-38; perhaps you are not aware that the Navy had let a contract to Collins to develop the ARC-38 in 1952?  The Navy had also previously funded Collins for the development of the AN/ARC-26 AM transceiver   The Navy issued this contract, worth a million dollars, in 1947.  It was cancelled when the prototype was evaluated in 1952.  The ARC-26 was the Navy's answer to the ARC-21 but evidently Collins had less luck with this design then RCA had had with the ARC-21.  The first Congressional investigation report also noted that Collins had commercialized much of the ARC-38, minus the SMO, in the form of the 618S-1.  What is common knowledge about the ARC-38 and the 618S-1 is not verified in the official record.

 

What caused the demise of the ARC-21 was the changeover from AM to SSB in the late 1950's and early 1960's.  As for the lack of reliability of the ARC-21 and the longevity of the ARC-65, it should be mentioned that they are practically the same radio.  Yes one is DSB and the other SSB but the change was accomplished without much of a redesign.  Both share better then 90% of the DNA of subminiature tubes and relays.  At least two modules are directly exchangeable between the two transceivers.  See the tube data below.  Bold type numbers are exclusive to that particular transceiver, all other tube types are also found in the other set.

 

ARC-21

Type         Totals      Description:

0A2           1 ea        150v VRT

0B2           1 ea        108v VRT

2E26          2 ea        10Watt pentode

3B22          1 ea        Full Wave rectifier

3B28          4 ea        HV diode

4-65A          4 ea        65Watt tetrode

5636A        16 ea        Dual Cont pentode

5643A        1 ea        thyratron

5670          1 ea        Twin diode

5687          2 ea        Double triode

5718          3 ea        Medium MU triode

5719A        2 ea        triode

5840A        14 ea        Sharp Cutoff pentode

5896A        8 ea        Twin diode

5899A        5 ea        Semi-Remote pentode

5902A        3 ea        Beam pentode

6021A        15 ea        Twin triode

991            1 ea          58v VRT

Grand total: 84 Tubes

76 / 84 x 100 = 90.5% of ARC-21 tube types are also used in the ARC-65

 

ARC-65

Type            Totals      Description:

0B2             1 ea         108v VRT

3B28            4 ea        HV diode

4X250F        2 ea        Power Tetrode

6CL6            2 ea        Power Pentode

5636S        14 ea        Dual Cont pentode

5636AS        2 ea        Dual Cont pentode

5643S          1 ea        thyratron

5670WA       1 ea        Twin diode

5687              2 ea        Double triode

5718S            3 ea        Medium MU triode

5719S            1 ea        triode

5840S            19 ea      Sharp Cutoff pentode

5896A            3 ea        Twin diode

5896S            4 ea        Twin diode

5899AS          6 ea        Semi-Remote pentode

5902AS          2 ea        Beam pentode

6021A            7 ea        Twin triode

6021S            12 ea       Twin triode

6021AS            1 ea        Twin triode

991                    1 ea        58v VRT

Grand total: 88 Tubes

84 / 88 x 100 = 95.5% of the ARC-65 tube types are also used in the ARC-21

 

 The only difference beyond circuit changes for a balanced modulator, a linear PA, a narrow bandwidth mechanical filter, a product detector, and a higher accuracy Reference Oscillator is the type number suffix of tubes used in both sets.  As an example, the RCA preliminary ARC-21 manual called for a JAN 5840, the ARC-21 military manual, which covered the improved ARC-21, called for a 5840A and the ARC-65 manual calls for a 5840S.  The only real difference between these three vacuum tubes is the level of testing done after the tube was manufactured.  Like Papa John says:  Better ingredients, better pizza!

 

Regards,

Jim

 

 

 

From:  <mailto:milsurplus-bounces at mailman.qth.net> milsurplus-bounces at mailman.qth.net < <mailto:milsurplus-bounces at mailman.qth.net> milsurplus-bounces at mailman.qth.net> On Behalf Of Mike Morrow
Sent: Thursday, October 29, 2020 6:59 AM
To:  <mailto:milsurplus at mailman.qth.net> milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

It's interesting that the principle post-WWII aircraft HF-AM set selected by the USAF was the RT-128A/ARC-21 along with the R-224/ARR-36 aux receiver.  This RCA-made equipment had a very troubled history of of unreliability and extreme procurement costs that prompted U.S. Congressional investigation.  The extended delays for introduction of this equipment caused the WWII-vintage AN/ARC-8 (T-47A/ART-13 and BC-348-*) to be continued in service and for USAF purchases of many Collins 618S-1 sets to fill in for the missing AN/ARC-21.

 

During the same period, the USN chose the Collins RT-311/ARC-38 and R-648/ARR-41 aux receiver to replace its AN/ARC-25 (T-47/ART-13 and R-105A/ARR-15).  From its introduction this Collins equipment was far more reliable and cost a small fraction of the USAF's RCA gear.

 

When SSB became the desired mode, RCA developed a USB conversion of the RT-128A/ARC-21 into the RT-400/ARC-65.  It appears RCA saw a similar opportunity and developed the  USB conversion of the RT-311/ARC-38 into the RT-594/ARC-38A.  Although very complex, apparently the RT-594 was successful enough to remain flying for another decade and more.  Older USN aircraft with the AN/ARC-38A often retained it after an RT-648/ARC-94 (Collins 618T-2) was installed.

 

It would be interesting to know if RCA used the same team to develop both the RT-400 and RT-594.  All things considered, I'd say they were very successful in military service. 

 

Mike / KK5F

-----Original Message----- 
From: Ulrich N Fierz via Milsurplus 
Sent: Oct 29, 2020 3:53 AM 

Good morning Ray

 

here I have a 618S-1 (no original control head) and a long time considered the ARC-38A, but I think I can easily confirm: the A is a nightmare... 

 

Good luck with your many radios

 

Ulrich  hb9aik - vk2ani

 

Ulrich Fierz

8044 Zurich/Switzerland

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net <mailto:Milsurplus at mailman.qth.net> 

This list hosted by: http://www.qsl.net <http://www.qsl.net/> 
Please help support this email list: http://www.qsl.net/donate.html

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201102/e3d5245c/attachment-0001.html>

From frledda at att.net  Mon Nov  2 17:01:06 2020
From: frledda at att.net (frledda at att.net)
Date: Mon, 2 Nov 2020 16:01:06 -0600
Subject: [Milsurplus] Arc-38A as modified by RCA
In-Reply-To: <052501d6b156$97f70360$c7e50a20$@att.net>
References: <1258479195.379.1603969161058@wamui-abby.atl.sa.earthlink.net>	<06a101d6ae19$91e57dc0$b5b07940$@bellsouth.net>	<585093689.729142.1604260200512@mail.yahoo.com>	<914841023.751350.1604273182645@mail.yahoo.com>	<2113409776.795718.1604303013716@mail.yahoo.com>	<03f301d6b129$7ed5e1d0$7c81a570$@att.net>	<1187432402.907742.1604344521641@mail.yahoo.com>
	<052501d6b156$97f70360$c7e50a20$@att.net>
Message-ID: <001c01d6b163$ab944d30$02bce790$@att.net>

Jim, 

 

One more thing, I have seen products go out to mass production prematurely, quite few times.  

 

Reasons were: longer than expected design cycles, suppliers being late, contractual commitments, not well evaluated scope changes and, of course, the most important one ?booking revenue?.    

 

Best, Francesco K5URG

 

From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of frledda at att.net
Sent: Monday, November 2, 2020 2:28 PM
To: 'Jim Whartenby' <old_radio at aol.com>; Milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

Jim,

 

On this particular topic, we will agree to disagree.  

 

There is a difference between reliability of a component and its spec variance.  I believe that the ARC-21/65 needed ?some selected components? and the 5814S is the proof.

 

The ARC-38 did not suffer from this, as any garden variety component worked in it. When I worked at Collins, we tested new designs with components form different production batches and suppliers to make evaluate the design stability. Critical circuits were validated by exercising the possible variances of each components.  We temp tested and exceeded the temp/voltage ranges by 30%. If it did not work, we were going back to drawing board.

 

As a design manager and later design executive, my approach was to force my designers to use the standard supply chain components, and only in special cases, I allowed to use selected components.  A selected component costs multiple times as much as a standard production one, and creates supply chain issues (new PN, new procurement, more cost, more inventory, more taxes and unhappy customers). 

 

Already in the 70s, designers at Collins (HP and others) designers were discouraged from designing products with tuning/adjustments like pots (etc.), as they required extra manufacturing time. This approach required better quality designs.

 

I think that my feelings about the ARC-21/65 are not very positive, as I think that this product was half-baked when it entered production.  Later efforts improved the product.

 

Again, I enjoyed this conversation, but forgive me for disagreeing with you ?

 

Best, Francesco

 

 

 

 

 

From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Jim Whartenby via Milsurplus
Sent: Monday, November 2, 2020 1:15 PM
To: milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

Francesco

 

The pizza remark was done "tong in cheek" but it does indicate that better components makes for a better product which was what I was aiming for.

 

"...the need for screened components is a clear indication of a marginal design."

Don't know what to make of this.  Clearly, a 5654W is not the same as a 6AK5 even though they may preform the same in most circuits.  If the specification calls for a 5654W then one has automatically screened that component.  It has already gone through the various tests that have weeded out inferior examples.  In the early 1950's, these types of component specifications did not exist.  Commercial as opposed to JAN components were all that were then available.  

 

The experience in addressing the shortfalls in the ARC-21 program, among many other programs of that time period, led to the research into failure analysis and the creation of various component specifications needed to increase the quality of components and by extension, the reliability of the electronics system.  Clearly, the ARC-21 met all design specifications in the original contract; the total build as of 20 April 1961 was 5,394 sets.  The issue was that when the system was first installed in the harsh B-47 environment, the life expectancy fell short.  Those issues that caused the low reliability were addressed and corrected.

 

In today's world, almost all of the high-rel component specifications have been rescinded because commercial components now are of vastly higher quality then those made in the 1950's.  That is one of the many pitfalls in looking back 70 odd years from the perspective of the year 2020.  The products made back then fall short of today's expectations but at the time, they were marvelous.

 

"...it is almost and (sic) unfair comparison, but it needs to be made".

If it is an unfair comparison, why not compare the ARC-21 with it's contemporaries?

 

.                           ARC-21            618S          ARC-38

Freq range:          2-24 mc         2-25 mc        2-25 mc

Channels:             44,000          144                35,250

Ch. spacing:         500 cycles      NA               500 / 1000* cycles

Freq. Stability:      0.0015%      0.007%          0.01%

Altitude:               50k feet         50k feet         50k feet  (See Note below)

Op. temp:             -55C/+85C      Unk               Unk

RF power:             >100 watts      >90 watts*   >90 watts*

freq setup:             direct input      crystal          code book

Weight**              136 lbs             64 lbs          73 lbs.

*Frequency dependent, high frequency spec shown

**R/T + mount, approximately half of the ARC-21 mount is part of the R/T unit

Note:  The 618S or ARC-38 operating at 50,000 feet seems a bit optimistic to me. Air pressure is down to about 11.5% that of sea level. How is the R/T unit cooled at this altitude? Neither the R/T unit nor the mounting rack have fans to move air. What about condensation of water on the modules as the aircraft climbs to operational altitude from a hot and humid airfield?

 

The issue really is that being the first to do something is much, much harder then when you can benefit from the mistakes made by those who came before you.  It is so much easier to play catch-up then to weed through all of the possibilities to find the path to a successful design.  Many times it is not possible to get to do a "do-over."  I am quite sure that the RCA designers would have preferred a second chance at the ARC-21 design.  There is always room for improvement, isn't there?

 

Regards,

Jim

 

I wonder why people argue over the 10% of their differences and ignore the 90% they agree on?

 

-----Original Message-----
From: frledda at att.net <mailto:frledda at att.net> 
To: milsurplus at mailman.qth.net <mailto:milsurplus at mailman.qth.net> 
Sent: Mon, Nov 2, 2020 9:04 am
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

I don?t buy ?the better ingredients, better pizza? story.

 

Having been a design engineer at Collins and other companies, the need for screened components is a clear indication of a marginal design. I can only imagine the supply chain perturbations and cost associated with supplying the 5814S and other screened components.  

 

People may say that being the ARC-21 very complex (84 tubes and a large number of relays), this kind of instability and reliability is normal.  I beg to differ, based on my experience.  I was a system engineer for NATO on the Nike Hercules missile system, and the systems had thousands of tubes and relays, and never had to select components to make  it work.

 

Being the ARC-58 much more modern than the ARC-21/65, it is almost and unfair comparison, but it needs to be made.

 

ARC-65 vs ARC-58

Weight 245lb vs 175lbs

Volume 9.5ft^3 vs 5.85ft^3

Frequency range 2-24 MHz vs 2-29.999 MHz

Frequency Stability 150Hz @10MHz vs 10Hz @10MHz

Transmitter power  230W PEP SSB vs 900 MHz PEP SSB

MTBF 120h vs 290h

 

The Univac antenna coupler was a good coupler but inferior in reliability to the 180R-6, due to the integration of the servo amps into the coupler itself. The servo amps used magamps that suffered from temperature extremes, Collins?s choice to keep the controller in the pressurized vessel was key for their better reliability.  Also, the Collins 180R-6 used a low pass filter architecture that further reduced higher harmonics. The Univac used high pass filter architecture 

 

Best, Francesco K5URG

 

 

 

From: milsurplus-bounces at mailman.qth.net <mailto:milsurplus-bounces at mailman.qth.net>  <milsurplus-bounces at mailman.qth.net <mailto:milsurplus-bounces at mailman.qth.net> > On Behalf Of Jim Whartenby via Milsurplus
Sent: Monday, November 2, 2020 1:44 AM
To: 
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

Mike

I do not agree with you that the ARC-21 had a history of unreliability.  It certainly was not much different then any other system found in the B-47 bomber other then the K Bombing and Navigation System.  This system weighed in at over a thousand pounds and used 370 vacuum tubes and an even higher number of relays.  MTBF for the BNS was so low that spare modules were carried in the B-47 Navigator's compartment.

 

It is rarely mentioned that the AN/ARC-21 was designed for use in the B-47 where it was mounted in the rear of the aircraft, aft of the rear landing gear, along with the ARC-27 UHF transceiver.  This location is where vibration and temperature extremes work it's magic.  Any HF transceivers used in place of the ARC-21 were installed in support aircraft such as the KC-97 or KC-135, not in a B-47.  No other HF transceiver available at this time was able to operate under the extreme conditions found in the B-47.  

 

The ARC-21 did have initial teething problems not unlike many other "state of the art" systems found in the B-47 or other aircraft.  But these problems were addressed and corrected as the source of the problems were determined and the failure mechanisms understood.  This was verified in the final report of "Project Big Eva" An Accelerated Service Test of Radio Set AN/ARC-21 in March, 1955.

 

There were two U.S. Congressional investigations concerning the ARC-21 of which I am aware.  The first was titled "Air Force Development and Procurement of the AN/ARC-21 Airborne Radio Transceivers," March 29, 1954.  The second was titled "Examination of the Pricing of the AN/ARC-21 Receiver-Transmitters," June 30, 1961.

 

The first investigation was about the Air Force procuring the ARC-21 before sufficient testing had been done on the prototype to verify performance.  The Air Force was in a panic with the build up of forces to fight the Korean War.  Congress was not critical of the problems facing the Air Force concerning the build up but they were concerned with the contracts let by the Air Force to RCA for an initial 3,900 sets and a follow on order for another 1,843 sets all before the delivery of the ARC-21 prototype for acceptance testing!  

 

The second investigation on pricing concerned the heat exchanger / pressure vessel which formed the outer case of the ARC-21.  This was the single costliest component of the ARC-21.  There was a $300 discrepancy between what RCA initially told the Air Force what it would cost and what RCA actually paid the contractor who made the heat exchanger.  Oh, well!

 

By the time of this first Congressional investigation, about 700 or so sets of the AN/ARC-21 had been delivered to the Air Force.  The problem with reliability was mainly due to vacuum tube and relay failures due to infant mortality and a lack of sufficient process control in the manufacturing of subminiature tubes and relays.  This is all well documented.  It should also be mentioned that there are approximately 100 relays used in the ARC-21.  The same number of relays are also used in the ARC-65.

 

There were also issues with other components such as resistors, capacitors and such but the main issue was with vacuum tubes and relays.  While the component manufacturers worked on improving their designs, overall reliability of the ARC-21 was improved with 100% component testing before module assembly.  This weeded out infant mortality failures of vacuum tubes and relays.  Completed ARC-21 sets then went through a 200 continuous hour operational test which included shake, rattle and roll while operating at elevated temperature.  Any failure found during the test returned the repaired ARC-21 to the beginning of the 200 hour test.  This forced the early failures and brought the reliability up to the point where the "Project Big Eva" testing program had verified that reliability was on par with other electronic systems used in the B-47.

 

With respect to your comments about the Navy choosing the ARC-38; perhaps you are not aware that the Navy had let a contract to Collins to develop the ARC-38 in 1952?  The Navy had also previously funded Collins for the development of the AN/ARC-26 AM transceiver   The Navy issued this contract, worth a million dollars, in 1947.  It was cancelled when the prototype was evaluated in 1952.  The ARC-26 was the Navy's answer to the ARC-21 but evidently Collins had less luck with this design then RCA had had with the ARC-21.  The first Congressional investigation report also noted that Collins had commercialized much of the ARC-38, minus the SMO, in the form of the 618S-1.  What is common knowledge about the ARC-38 and the 618S-1 is not verified in the official record.

 

What caused the demise of the ARC-21 was the changeover from AM to SSB in the late 1950's and early 1960's.  As for the lack of reliability of the ARC-21 and the longevity of the ARC-65, it should be mentioned that they are practically the same radio.  Yes one is DSB and the other SSB but the change was accomplished without much of a redesign.  Both share better then 90% of the DNA of subminiature tubes and relays.  At least two modules are directly exchangeable between the two transceivers.  See the tube data below.  Bold type numbers are exclusive to that particular transceiver, all other tube types are also found in the other set.

 

ARC-21

Type         Totals      Description:

0A2           1 ea        150v VRT

0B2           1 ea        108v VRT

2E26          2 ea        10Watt pentode

3B22          1 ea        Full Wave rectifier

3B28          4 ea        HV diode

4-65A          4 ea        65Watt tetrode

5636A        16 ea        Dual Cont pentode

5643A        1 ea        thyratron

5670          1 ea        Twin diode

5687          2 ea        Double triode

5718          3 ea        Medium MU triode

5719A        2 ea        triode

5840A        14 ea        Sharp Cutoff pentode

5896A        8 ea        Twin diode

5899A        5 ea        Semi-Remote pentode

5902A        3 ea        Beam pentode

6021A        15 ea        Twin triode

991            1 ea          58v VRT

Grand total: 84 Tubes

76 / 84 x 100 = 90.5% of ARC-21 tube types are also used in the ARC-65

 

ARC-65

Type            Totals      Description:

0B2             1 ea         108v VRT

3B28            4 ea        HV diode

4X250F        2 ea        Power Tetrode

6CL6            2 ea        Power Pentode

5636S        14 ea        Dual Cont pentode

5636AS        2 ea        Dual Cont pentode

5643S          1 ea        thyratron

5670WA       1 ea        Twin diode

5687              2 ea        Double triode

5718S            3 ea        Medium MU triode

5719S            1 ea        triode

5840S            19 ea      Sharp Cutoff pentode

5896A            3 ea        Twin diode

5896S            4 ea        Twin diode

5899AS          6 ea        Semi-Remote pentode

5902AS          2 ea        Beam pentode

6021A            7 ea        Twin triode

6021S            12 ea       Twin triode

6021AS            1 ea        Twin triode

991                    1 ea        58v VRT

Grand total: 88 Tubes

84 / 88 x 100 = 95.5% of the ARC-65 tube types are also used in the ARC-21

 

 The only difference beyond circuit changes for a balanced modulator, a linear PA, a narrow bandwidth mechanical filter, a product detector, and a higher accuracy Reference Oscillator is the type number suffix of tubes used in both sets.  As an example, the RCA preliminary ARC-21 manual called for a JAN 5840, the ARC-21 military manual, which covered the improved ARC-21, called for a 5840A and the ARC-65 manual calls for a 5840S.  The only real difference between these three vacuum tubes is the level of testing done after the tube was manufactured.  Like Papa John says:  Better ingredients, better pizza!

 

Regards,

Jim

 

 

 

From:  <mailto:milsurplus-bounces at mailman.qth.net> milsurplus-bounces at mailman.qth.net < <mailto:milsurplus-bounces at mailman.qth.net> milsurplus-bounces at mailman.qth.net> On Behalf Of Mike Morrow
Sent: Thursday, October 29, 2020 6:59 AM
To:  <mailto:milsurplus at mailman.qth.net> milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Arc-38A as modified by RCA

 

It's interesting that the principle post-WWII aircraft HF-AM set selected by the USAF was the RT-128A/ARC-21 along with the R-224/ARR-36 aux receiver.  This RCA-made equipment had a very troubled history of of unreliability and extreme procurement costs that prompted U.S. Congressional investigation.  The extended delays for introduction of this equipment caused the WWII-vintage AN/ARC-8 (T-47A/ART-13 and BC-348-*) to be continued in service and for USAF purchases of many Collins 618S-1 sets to fill in for the missing AN/ARC-21.

 

During the same period, the USN chose the Collins RT-311/ARC-38 and R-648/ARR-41 aux receiver to replace its AN/ARC-25 (T-47/ART-13 and R-105A/ARR-15).  From its introduction this Collins equipment was far more reliable and cost a small fraction of the USAF's RCA gear.

 

When SSB became the desired mode, RCA developed a USB conversion of the RT-128A/ARC-21 into the RT-400/ARC-65.  It appears RCA saw a similar opportunity and developed the  USB conversion of the RT-311/ARC-38 into the RT-594/ARC-38A.  Although very complex, apparently the RT-594 was successful enough to remain flying for another decade and more.  Older USN aircraft with the AN/ARC-38A often retained it after an RT-648/ARC-94 (Collins 618T-2) was installed.

 

It would be interesting to know if RCA used the same team to develop both the RT-400 and RT-594.  All things considered, I'd say they were very successful in military service. 

 

Mike / KK5F

-----Original Message----- 
From: Ulrich N Fierz via Milsurplus 
Sent: Oct 29, 2020 3:53 AM 

Good morning Ray

 

here I have a 618S-1 (no original control head) and a long time considered the ARC-38A, but I think I can easily confirm: the A is a nightmare... 

 

Good luck with your many radios

 

Ulrich  hb9aik - vk2ani

 

Ulrich Fierz

8044 Zurich/Switzerland

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net <mailto:Milsurplus at mailman.qth.net> 

This list hosted by: http://www.qsl.net <http://www.qsl.net/> 
Please help support this email list: http://www.qsl.net/donate.html

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201102/d10a8724/attachment-0001.html>

From old_radio at aol.com  Mon Nov  2 18:12:15 2020
From: old_radio at aol.com (Jim Whartenby)
Date: Mon, 2 Nov 2020 23:12:15 +0000 (UTC)
Subject: [Milsurplus] Arc-38A as modified by RCA
In-Reply-To: <052501d6b156$97f70360$c7e50a20$@att.net>
References: <1258479195.379.1603969161058@wamui-abby.atl.sa.earthlink.net>
	<06a101d6ae19$91e57dc0$b5b07940$@bellsouth.net>
	<585093689.729142.1604260200512@mail.yahoo.com>
	<914841023.751350.1604273182645@mail.yahoo.com>
	<2113409776.795718.1604303013716@mail.yahoo.com>
	<03f301d6b129$7ed5e1d0$7c81a570$@att.net>
	<1187432402.907742.1604344521641@mail.yahoo.com>
	<052501d6b156$97f70360$c7e50a20$@att.net>
Message-ID: <597372454.972343.1604358735713@mail.yahoo.com>

FrancescoNo issues here about disagreements.? I am here to learn and share what I have discovered.

For whatever reason, I did not make the connection that the suffix "S" stood for "Selected" or "Special"; my bad.? Your comments now make perfect sense.

Raytheon supplied the 5840S subminiature tubes so I doubt that I will find out what "S" actually stood for.? ?Perhaps it was nothing more then just a microscopic visual inspection?? I know that visual inspections were part of the early process in getting a handle on what was happening to cause the ARC-21 reliability issues.? Debris and broken welds on the inside of the tube envelope were mentioned in the early reliability reports.? So perhaps I will take another look at them to see if there is a mention about the self inspection of tubes at Raytheon.

I have several examples of the ARC-21 here.? None are from the first 1952 contract of 3900 units.? All are from the third contract?and have serial numbers in the 4XXX range.? It appears that RCA did not start over at zero when supplying ARC-21's under new contracts.? So I would guess that all of the first contact ARC-21's became ARC-65's.? The ARC-21 to ARC-65 conversion article in the house pub "RCA Engineer" mentioned in passing that about 5000 ARC-21's were converted?to ARC-65's in the late 1950's.? The last ARC-21 build was changed to ARC-65 sets.? I don't know if this was the the fifth contract?or not.??

>From one of the congressional reports on the ARC-21:Firstproduction contract: AF33(038)-18325, Date: 1952, Quantity built:3900Secondproduction contract: AF33(600)-32331 Date: 1956, Quantity built: 121
Third production contract: AF33(600)-32926 Date: 1956, Quantity built: 380
Forthproduction contract: AF33(600)-33883, Date: 1956, Quantity built:551
Fifth production contract:AF33(600)-35867, Date: 1957. Quantity built: 442
Total built as of 20 April 1961: 5,394I have no idea of how many contracts were let for the ARC-65 or how many were built.


Francesco, when this Covid thing gets resolved, hopefully we will bump into each other again at a Texas Hamfest!

Regards,Jim

I wonder why people argue over the 10% of their differences and ignore the 90% they agree on?

-----Original Message-----
From: frledda at att.net
To: 'Jim Whartenby' <old_radio at aol.com>; Milsurplus at mailman.qth.net
Sent: Mon, Nov 2, 2020 2:27 pm
Subject: RE: [Milsurplus] Arc-38A as modified by RCA

<!--#yiv3171593848 _filtered {} _filtered {} _filtered {} _filtered {} _filtered {}#yiv3171593848 #yiv3171593848 p.yiv3171593848MsoNormal, #yiv3171593848 li.yiv3171593848MsoNormal, #yiv3171593848 div.yiv3171593848MsoNormal {margin:0in;font-size:11.0pt;font-family:"Calibri", sans-serif;}#yiv3171593848 a:link, #yiv3171593848 span.yiv3171593848MsoHyperlink {color:blue;text-decoration:underline;}#yiv3171593848 span.yiv3171593848EmailStyle29 {font-family:"Calibri", sans-serif;color:windowtext;}#yiv3171593848 .yiv3171593848MsoChpDefault {font-family:"Calibri", sans-serif;} _filtered {}#yiv3171593848 div.yiv3171593848WordSection1 {}-->Jim, ?On this particular topic, we will agree to disagree.?  ?There is a difference between reliability of a component and its spec variance. ?I believe that the ARC-21/65 needed ?some selected components? and the 5814S is the proof. ?The ARC-38 did not suffer from this, as any garden variety component worked in it. When I worked at Collins, we tested new designs with components form different production batches and suppliers to make evaluate the design stability. Critical circuits were validated by exercising the possible variances of each components.? We temp tested and exceeded the temp/voltage ranges by 30%. If it did not work, we were going back to drawing board. ?As a design manager and later design executive, my approach was to force my designers to use the standard supply chain components, and only in special cases, I allowed to use selected components. ?A selected component costs multiple times as much as a standard production one, and creates supply chain issues (new PN, new procurement, more cost, more inventory, more taxes and unhappy customers).  ?Already in the 70s, designers at Collins (HP and others) designers were discouraged from designing products with tuning/adjustments like pots (etc.), as they required extra manufacturing time. This approach required better quality designs. ?I think that my feelings about the ARC-21/65 are not very positive, as I think that this product was half-baked when it entered production.? Later efforts improved the product. ?Again, I enjoyed this conversation, but forgive me for disagreeing with you ? ?Best, Francesco
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201102/f720d489/attachment.html>

From RAFANTINI at salisbury.edu  Tue Nov  3 11:16:41 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Tue, 3 Nov 2020 16:16:41 +0000
Subject: [Milsurplus] AN/ARC-21 or 65
Message-ID: <BY5PR02MB675548F96EF55E5B0DA19075B8110@BY5PR02MB6755.namprd02.prod.outlook.com>

There are enumerable videos AN/ARC-8 (BC-348/ART-13) in operation out there, several of the ARC-94/RT-618 and I have a video up for my AN/ARC-38 transceiver at work, But most of us have never seen and even fewer saw a working ANARC-21 or 65 so if you are the owner of such radios you almost have an obligation to get it working, on the air and do a video of it for all of us.

The world wants to see!

Ray F/KA3EKH


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201103/602c2cc3/attachment-0001.html>

From scr287 at att.net  Tue Nov  3 11:47:10 2020
From: scr287 at att.net (Jack Antonio)
Date: Tue, 3 Nov 2020 11:47:10 -0500
Subject: [Milsurplus] AN/ARC-21 or 65
In-Reply-To: <BY5PR02MB675548F96EF55E5B0DA19075B8110@BY5PR02MB6755.namprd02.prod.outlook.com>
References: <BY5PR02MB675548F96EF55E5B0DA19075B8110@BY5PR02MB6755.namprd02.prod.outlook.com>
Message-ID: <b5b08a4a-133b-12b9-ba9a-894c842f4a26@att.net>

First, the usual disclaimer. No connections with the
seller, except that I have been a customer.

For those looking for ARC-21 parts and pieces, the
DY-50/ARC-21 dynamotor is on eBay, and has been
for awhile.

Item number 164360580802

Jack Antonio
WA7DIA


From RAFANTINI at salisbury.edu  Tue Nov  3 12:27:44 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Tue, 3 Nov 2020 17:27:44 +0000
Subject: [Milsurplus] AN/ARC-21 or 65
Message-ID: <BY5PR02MB67556B18A275FD6F39D65483B8110@BY5PR02MB6755.namprd02.prod.outlook.com>

Wow, a Trippel headed DY-50 Dyno assembly! Thought the ARC-21/65 was a three phase 120 volts 400 cycle set? Was there also a version that ran from DC?
Think but may be wrong that the B-36 was the first strategic bomber designed from the ground up to use 120-volt 400 cycle distribution and somehow assumed the ARC-21 was built for use in that aircraft.

Ray F/KA3EKH

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201103/9136642d/attachment.html>

From scr287 at att.net  Tue Nov  3 16:38:31 2020
From: scr287 at att.net (Jack Antonio)
Date: Tue, 3 Nov 2020 16:38:31 -0500
Subject: [Milsurplus] was AN/ARC-21 or 65 but back to the ARC-38
In-Reply-To: <BY5PR02MB67556B18A275FD6F39D65483B8110@BY5PR02MB6755.namprd02.prod.outlook.com>
References: <BY5PR02MB67556B18A275FD6F39D65483B8110@BY5PR02MB6755.namprd02.prod.outlook.com>
Message-ID: <0f83749d-9c8e-94c3-4ff0-84750846d4ee@att.net>

On 11/3/2020 12:27 PM, Ray Fantini wrote:
> Wow, a Trippel headed DY-50 Dyno assembly! Thought the ARC-21/65 was a 
> three phase 120 volts 400 cycle set? Was there also a version that ran 
> from DC?


Going back to the ARC-38 and 618S-1 for a bit.

The ARC-38 and 618S series supply generates
Hi Voltage from dynamotor, and the other voltages
from 120V 400 cycle 1 phase. 28V is supplied
by the aircraft to run the dynamotor, filaments
and control circuitry. These are the DY-118 and
416W-1 and from what I can tell are identical.

There *might* be another supply, the 416W-3
which generates its voltages from 120V 400 cycle
3 phase. But whether or not it generates 28VDC
internally, or uses 28VDC from the aircraft, I
don't know. I don't have any documentation for
it. (Anyone have a copy of the manual for it?)

In fact, I don't know for sure that it is an
alternate supply for the 618S-1, I'm only
going on the fact that it fits the rack, the
connector is the same, and it carries
the 416W type number.

I have one of these, but don't have any
3 phase 400 cycle to play with.

Which brings up another question.

Is there a document anywhere which describes the
Collins nomenclature scheme? Commercial receivers
seem to the 51 series, amateur receivers were
75, and 618 seem to aircraft transceivers.

But is there a master list of what is what?

Jack Antonio
WA7DIA




From RAFANTINI at salisbury.edu  Wed Nov  4 16:09:32 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Wed, 4 Nov 2020 21:09:32 +0000
Subject: [Milsurplus] ARC-38 trivia!
Message-ID: <BY5PR02MB67557F7F70C9E483A833DC34B8EF0@BY5PR02MB6755.namprd02.prod.outlook.com>

The ARC-38, a and 618S only use the dynamotor in the transmit mode or when in CW it runs the whole time you're in CW. Weird trivia about that family of radios. The filaments are all powered from the 28-volt DC bus on the airplane. But the radio will not receive or work unless you have 120 volts @ 400 cycles, you need the 400 cycles source for running the servo assemblies in the slug rack and SMO if it's a 38 but the 400-cycle source also feeds a half wave voltage doubler that provides the B+ for the receiver and SMO assemblies. The dynamotor only provides the high voltages for the modulator and PA assemblies. The same thing also happens in the 618T family of radios so if you have no source 400 cycles you don't have a radio.  More trivia! I have a habit of pulling the 120-volt 400 cycle source from the input of the servo systems and 180L tuner after the radio sets itself on channel and tunes itself. The radio works just fine without the AC on the servo systems and there are two separate AC feeds, one for the servo and one for the receiver power supply so it's easy to do.
Extra bonus points: the use of a half wave voltage doubler without any transformer directly from the 120-volt source was also common practice in television sets of the fifties and early sixties. On a TV set it results in a possibly hot chassis depending on how its plugged in but in a aircraft one side of the AC system is grounded and everything is hardwired so that won't happen.

Ray F/KA3EKH

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201104/144f6bb1/attachment.html>

From old_radio at aol.com  Wed Nov  4 18:02:47 2020
From: old_radio at aol.com (Jim Whartenby)
Date: Wed, 4 Nov 2020 23:02:47 +0000 (UTC)
Subject: [Milsurplus] AN/ARC-21 or 65
In-Reply-To: <BY5PR02MB67556B18A275FD6F39D65483B8110@BY5PR02MB6755.namprd02.prod.outlook.com>
References: <BY5PR02MB67556B18A275FD6F39D65483B8110@BY5PR02MB6755.namprd02.prod.outlook.com>
Message-ID: <1740361978.1392852.1604530967835@mail.yahoo.com>

RayThe ARC-21 uses DC servo motor tuning.? There are no solid state devices, not even diodes, tubes are the only amplifiers used.? The upgrade to ARC-65 uses 400 cycle single phase power but I have yet to find out exactly where it is used.? Seems that it is easy for me to get lost following wires through several pages of schematics!? The only difference between the DY-50/ARC-21 and the DY-153/ARC-65, that I have noticed, is the addition of a 115v to 28v 400 cycle transformer drawing 0.3 amps during receive, transmitting and tuning.? My gut feeling is that it supplies negative grid bias to the 4CX250F tubes in the power amplifier.Jim

I wonder why people argue over the 10% of their differences and ignore the 90% they agree on?

-----Original Message-----
From: Ray Fantini <RAFANTINI at salisbury.edu>
To: milsurplus at mailman.qth.net <milsurplus at mailman.qth.net>
Sent: Tue, Nov 3, 2020 11:27 am
Subject: [Milsurplus] AN/ARC-21 or 65

 #yiv2021248826 #yiv2021248826 -- filtered {}#yiv2021248826 filtered {}#yiv2021248826 p.yiv2021248826MsoNormal, #yiv2021248826 li.yiv2021248826MsoNormal, #yiv2021248826 div.yiv2021248826MsoNormal {margin:0in;margin-bottom:.0001pt;font-size:11.0pt;font-family:sans-serif;}#yiv2021248826 a:link, #yiv2021248826 span.yiv2021248826MsoHyperlink {color:#0563C1;text-decoration:underline;}#yiv2021248826 a:visited, #yiv2021248826 span.yiv2021248826MsoHyperlinkFollowed {color:#954F72;text-decoration:underline;}#yiv2021248826 span.yiv2021248826EmailStyle17 {font-family:sans-serif;color:windowtext;}#yiv2021248826 .yiv2021248826MsoChpDefault {font-family:sans-serif;}#yiv2021248826 filtered {}#yiv2021248826 div.yiv2021248826WordSection1 {}#yiv2021248826 Wow, a Trippel headed DY-50 Dyno assembly! Thought the ARC-21/65 was a three phase 120 volts 400 cycle set? Was there also a version that ran from DC? Think but may be wrong that the B-36 was the first strategic bomber designed from the ground up to use 120-volt 400 cycle distribution and somehow assumed the ARC-21 was built for use in that aircraft.  ? Ray F/KA3EKH  ? ______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201104/3814566a/attachment-0001.html>

From RAFANTINI at salisbury.edu  Thu Nov  5 10:21:12 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Thu, 5 Nov 2020 15:21:12 +0000
Subject: [Milsurplus] Able Archer 83 at Fort Miles
Message-ID: <BY5PR02MB67556D2DD0DA2313A65DE982B8EE0@BY5PR02MB6755.namprd02.prod.outlook.com>

On Saturday November the 21st and Sunday the 22nd we will be having the annual Able Archer 83 W3A event. This year we will be operating from the Fort Miles facility located in Delaware's Cape Henlopen State park.
The relevance or connection to Fort Miles and Able Archer 83 is that from the early sixties until its decommissioning in the early eighties the Navy operated a SOSUS operation from that location at what was then known as NAVFAC Lewes.
I will be dragging the mutt (M-151A1) there and intend to operate both the MMRCG and the M&S nets from the mutt and am also looking at doing RTTY 850Hz shift on 7080 using the event call "W3A" and would like to know what interest there is with maybe doing a TTY net at 1400 or 1500 hours local?
Also, this can be an opportunity to do a backpack or field exercise on Sunday? Will have equipment for 51.0, 5357 (USB) and 3885 AM portable and if we can get anyone to get out of there house and come to the park maybe you can put all this equipment you have for field operation to use in the field.
Cape Henlopen State park is around six thousand acres with miles of trails, camping, fishing and the beaches along with the Fort Miles complex where in addition to visiting AA83 you can visit the artillery park, see the 16" gun from the Missouri or take a tour of the battery 519 bunker, they do beat you down for $5 for the bunker tour. That's all operated by the Historical group and we don't have anything to do with them so can't get you in for free.
If there is any interest in doing a field exercise lets try to work out what frequencies and times would be best, we got two weeks to get ready for this, its all an outdoor covid safe activity and if we can get at least one or two more people to come out I will bring out my field gear and take part.

Link for Cape Henlopen State Park:
https://destateparks.com/Beaches/CapeHenlopen

Link for Able Archer 83 W3A event:
https://sites.google.com/site/ablearcher1983w3a/


Ray F/KA3EKH
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201105/e9022d4c/attachment.html>

From wcprops at vt.edu  Fri Nov  6 11:34:54 2020
From: wcprops at vt.edu (William Props)
Date: Fri, 6 Nov 2020 11:34:54 -0500
Subject: [Milsurplus] Free RBA/RBB/RBC power supply
Message-ID: <CAFMEMPi1hSkSucrry5fz2WRH3wcceH4_EqvpZJR2fEivLCkG+A@mail.gmail.com>

I have an RBA/RBB/RBC power supply free for pickup. It's approximately 30
mins south of Harrisonburg, VA.

It is dirty and in poor condition. I stuck some tubes in it, and it worked
for the short time it was tested. Comes without tubes. I can send pics if
interested.

Also have some RBA/RBB/RBC receivers and power supplies I would consider
selling.

Chris
W4SVA
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201106/c1ed8ab9/attachment.html>

From mjcal77 at yahoo.com  Fri Nov  6 17:17:03 2020
From: mjcal77 at yahoo.com (CL in NC)
Date: Fri, 6 Nov 2020 22:17:03 +0000 (UTC)
Subject: [Milsurplus] PRC113
References: <1066867080.1771131.1604701023767.ref@mail.yahoo.com>
Message-ID: <1066867080.1771131.1604701023767@mail.yahoo.com>

I have a buddy with a PRC113 and wanted to know about the dial backlight, what they are, LED or incandescent, type of bulb, or if there is a bulb at all involved.  He also has a low squeal or tone in the audio and wondered if that was a common problem and common fix.  Please tell me it is so I can tell him and he can fix it and not me fix it.

Charlie, W4MEC in NC

From wa5cab at cs.com  Sun Nov  8 03:10:54 2020
From: wa5cab at cs.com (Robert Downs)
Date: Sun, 8 Nov 2020 02:10:54 -0600
Subject: [Milsurplus] [Boatanchors] Mica compression trimmers?
In-Reply-To: <DM6PR11MB4332C6F6E521ED9155E4E464BF190@DM6PR11MB4332.namprd11.prod.outlook.com>
References: <ao57ucjuo3gdu636lqgc4hn1.1603725452430@email.lge.com>
	<DM6PR11MB4332C6F6E521ED9155E4E464BF190@DM6PR11MB4332.namprd11.prod.outlook.com>
Message-ID: <002f01d6b5a6$aee63790$0cb2a6b0$@com>

BTW, it also occurred to me tonight that the term "mica compression trimmer"
is actually misleading as the compression of the mica dielectric doesn't
have anything to do with how the things work.  A more correct but definitely
less convenient to write name for the things might be "mica and air
dielectric variable spacing trimmer capacitor". 

Also, I didn't realize until a few years ago that the mica trimmers also
came in a "butterfly" version and that many of us have at least one radio
that uses one.  The radio being a BC-611-A...E.

Robert Downs

-----Original Message-----
From: boatanchors-bounces at mailman.qth.net
[mailto:boatanchors-bounces at mailman.qth.net] On Behalf Of McDonald, J
Douglas
Sent: Monday, October 26, 2020 14:36
To: boatanchors; boatanchors at theporch.com; Milsurplus
Subject: Re: [Boatanchors] Mica compression trimmers?

Its all a matter of degree.

I've seen such things with two adjustments: one for capacity,
one for temperature coefficient, which goes through zero. That was done with
a bimetal strip.

Doug McDonald



From n4fs at eozinc.com  Sun Nov  8 11:41:29 2020
From: n4fs at eozinc.com (Mike Feher)
Date: Sun, 8 Nov 2020 11:41:29 -0500
Subject: [Milsurplus] [Boatanchors] Mica compression trimmers?
Message-ID: <091201d6b5ee$02433090$06c991b0$@eozinc.com>

Hi Robert - 

I believe your observation is wrong. Mica compression trimmers indeed do
have mica between the plates, so the compression is on the mica and not air.
Consequently you can obtain a higher capacitance for the same size as the
dielectric constant for air is 1 and for mica it is about 3 to 6. 73 - Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201108/c5c1dd8e/attachment.html>

From kd7jyk at earthlink.net  Sun Nov  8 15:19:53 2020
From: kd7jyk at earthlink.net (KD7JYK DM09)
Date: Sun, 8 Nov 2020 12:19:53 -0800
Subject: [Milsurplus] [Boatanchors] Mica compression trimmers?
In-Reply-To: <091201d6b5ee$02433090$06c991b0$@eozinc.com>
References: <091201d6b5ee$02433090$06c991b0$@eozinc.com>
Message-ID: <4b3c7520-6ad1-5098-dd45-bde6ee27ef53@earthlink.net>

> I believe your observation is wrong. Mica compression trimmers indeed do 
> have mica between the plates, so the compression is on the mica and not 
> air. Consequently you can obtain a higher capacitance for the same size 
> as the dielectric constant for air is 1 and for mica it is about 3 to 6. 

And here I though rock didn't compress, and only the air-gap between the 
plates was changing relatively electrically, until the plates stopped. 
I do however, recall a saying of squeezing blood from a stone, so maybe 
that's how they work, but I can't imagine it designed to shatter 
eisenglass, bend plates, strip screws, and crack the body, for that last 
little uuF.  I figured the mica was the dielectric to increase the 
operating voltage...

Kurt


From n4fs at eozinc.com  Sun Nov  8 17:04:29 2020
From: n4fs at eozinc.com (Mike Feher)
Date: Sun, 8 Nov 2020 17:04:29 -0500
Subject: [Milsurplus] [Boatanchors] Mica compression trimmers?
In-Reply-To: <4b3c7520-6ad1-5098-dd45-bde6ee27ef53@earthlink.net>
References: <091201d6b5ee$02433090$06c991b0$@eozinc.com>
	<4b3c7520-6ad1-5098-dd45-bde6ee27ef53@earthlink.net>
Message-ID: <09af01d6b61b$217e5cf0$647b16d0$@eozinc.com>

Yes, mica indeed increases the operating voltage for the same plate spacing.
That is why it was used in early spark transmitters along with glass. It is
called a mica compression trimmer because mica is used as an insulator
between plates so they do not short. Obviously, mica is not compressed.
Neither is air in air variables. 73 - Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115

-----Original Message-----
From: milsurplus-bounces at mailman.qth.net
<milsurplus-bounces at mailman.qth.net> On Behalf Of KD7JYK DM09
Sent: Sunday, November 8, 2020 3:20 PM
To: 'milsurplus listserv' <milsurplus at mailman.qth.net>
Subject: Re: [Milsurplus] [Boatanchors] Mica compression trimmers?

> I believe your observation is wrong. Mica compression trimmers indeed 
> do have mica between the plates, so the compression is on the mica and 
> not air. Consequently you can obtain a higher capacitance for the same 
> size as the dielectric constant for air is 1 and for mica it is about 3 to
6.

And here I though rock didn't compress, and only the air-gap between the
plates was changing relatively electrically, until the plates stopped. 
I do however, recall a saying of squeezing blood from a stone, so maybe
that's how they work, but I can't imagine it designed to shatter eisenglass,
bend plates, strip screws, and crack the body, for that last little uuF.  I
figured the mica was the dielectric to increase the operating voltage...

Kurt

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


From gfsmith at cox.net  Sun Nov  8 17:16:40 2020
From: gfsmith at cox.net (Gordon Smith)
Date: Sun, 08 Nov 2020 14:16:40 -0800
Subject: [Milsurplus] [Boatanchors] Mica compression trimmers?
Message-ID: <mailman.477.1604873812.3112.milsurplus@mailman.qth.net>

Hi All,
Per the beginning of an ARCO Mica compression trimmer data sheet 
(edited slightly to help readability and available here: 
<https://datasheet.datasheetarchive.com/originals/scans/Scans-058/DSA2IH0026119.pdf>DSA2IH0026119.pdf 
): "variable compression mica trimming capacitors are produced by 
stacking mica dielectric capacitance units. A capacitor section 
consists of a thin film of mica between two spring loaded nonferrous 
metal conducting plates........A panhead adjusting screw.....is 
inserted through the center holes of the plates, the mica films and 
(a) threaded bushing. This screw provides variable compression on the 
formed metal plates, varying the plate separation capacitance."

Because of this style of construction technique, large capacitance 
trimmer units appear to be able to be modifiable to lower capacitance 
levels  by the removal of plates/mica sheets for lower capacitance 
levels. One ebay seller notes this in his listing : 
https://www.ebay.com/itm/315-Variable-Compression-Mica-Trimmer-Capacitor-Please-See-My-Note-/264803509560 


Hope this helps,

73, Gordon KJ6IKT

At 12:19 PM 11/8/2020, KD7JYK DM09 wrote:
>>I believe your observation is wrong. Mica compression trimmers 
>>indeed do have mica between the plates, so the compression is on 
>>the mica and not air. Consequently you can obtain a higher 
>>capacitance for the same size as the dielectric constant for air is 
>>1 and for mica it is about 3 to 6.
>
>And here I though rock didn't compress, and only the air-gap between 
>the plates was changing relatively electrically, until the plates 
>stopped. I do however, recall a saying of squeezing blood from a 
>stone, so maybe that's how they work, but I can't imagine it 
>designed to shatter eisenglass, bend plates, strip screws, and crack 
>the body, for that last little uuF.  I figured the mica was the 
>dielectric to increase the operating voltage...
>
>Kurt
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201108/8032827e/attachment.html>

From Kargo_cult at msn.com  Sun Nov  8 17:36:19 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sun, 8 Nov 2020 22:36:19 +0000
Subject: [Milsurplus] [Boatanchors] Mica compression trimmers?
In-Reply-To: <20201108221653.0C805149A9C7@mail.qsl.net>
References: <20201108221653.0C805149A9C7@mail.qsl.net>
Message-ID: <MWHPR22MB0269D3FE2475E489CD16122CE4EB0@MWHPR22MB0269.namprd22.prod.outlook.com>

I suppose the most accurate ( and unwieldy ) name would be "air and mica trimmers", since both are the dielectric.
Yes, you can pull apart the postage stamp sized trimmers. I have a slug of them in the 800 pF range, all removed from
boat radios where they were the low Z side of the pi-net. I wanted to get them down to say, 150 pF and this was quite
easy to do. Also if you need small pieces of mica, this is one source. 
-Hue 

From n2lxm at juno.com  Mon Nov  9 07:17:31 2020
From: n2lxm at juno.com (n2lxm at juno.com)
Date: Mon, 9 Nov 2020 07:17:31 -0500
Subject: [Milsurplus] Happy Birthday Marines
Message-ID: <AABR4YCWSAPZ7ZK2@smtpout04.vgs.untd.com>

To all My Marine Brothers and Sisters. Happy Birthday, 245 Years of
defending our freedoms. 

Semper Fidelis



                                                    Jeff N2LXM
                                          Amateur Radio Operator
                                                      American
                                                        Patriot
                                     Proud Father of Two US Marines
____________________________________________________________
Sponsored by https://www.newser.com/?utm_source=part&utm_medium=uol&utm_campaign=rss_taglines_more

Pompeo: Only Transition Will Be to Another Trump Term
http://thirdpartyoffers.juno.com/TGL3141/5fab0a9075482a903b04st04vuc1
Trump Has a Strategy to Keep Influence on GOP
http://thirdpartyoffers.juno.com/TGL3141/5fab0a9098b20a903b04st04vuc2
Common Theme Emerges in ObamaCare Arguments
http://thirdpartyoffers.juno.com/TGL3141/5fab0a90bcc24a903b04st04vuc3
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201109/c7cd490f/attachment.html>

From Kargo_cult at msn.com  Tue Nov 10 20:00:16 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Wed, 11 Nov 2020 01:00:16 +0000
Subject: [Milsurplus] GRC-9 construction ?
Message-ID: <MWHPR22MB02699F6C008FB98214EF1AC9E4E80@MWHPR22MB0269.namprd22.prod.outlook.com>

My brother says the curvature areas of the GRC-9 radio were built up out of some kind of "putty",
like to round out 90 degree conjunctions of metal surfaces. 
Anyone know what this "putty" consisted of ?
tnx
Hue Miller 

From scr287 at att.net  Fri Nov 13 10:51:54 2020
From: scr287 at att.net (Jack Antonio)
Date: Fri, 13 Nov 2020 10:51:54 -0500
Subject: [Milsurplus] Connector needed
References: <cc46e5c5-0992-8554-2c79-462eda1a7494.ref@att.net>
Message-ID: <cc46e5c5-0992-8554-2c79-462eda1a7494@att.net>

No luck at the usual places.

Anyone have a Navy 134 or Army
PL-65 they'd like to part with?

I'd prefer the 134 as this is for an
RU-19 project, but the PL-65 will
do fine.

This is the 6 contact connector for
the cable from the dynamotor to junction
box.

Thanks

Jack Antonio
WA7DIA

From pfthekan at gmail.com  Fri Nov 13 12:06:00 2020
From: pfthekan at gmail.com (Paul Thekan)
Date: Fri, 13 Nov 2020 09:06:00 -0800
Subject: [Milsurplus] Connector needed
In-Reply-To: <cc46e5c5-0992-8554-2c79-462eda1a7494@att.net>
References: <cc46e5c5-0992-8554-2c79-462eda1a7494.ref@att.net>
	<cc46e5c5-0992-8554-2c79-462eda1a7494@att.net>
Message-ID: <CAK4LMKOBqrk1gQzP13bzCZH1N+bJbvUpVnxDwyaR8NwZx7vitA@mail.gmail.com>

Hi Jack
 I came into some parts for my RU-19 and may have an extra 134 connector.
Will check when I get home and get back to you.
Paul
N6FEG


On Fri, Nov 13, 2020, 7:51 AM Jack Antonio <scr287 at att.net> wrote:

> No luck at the usual places.
>
> Anyone have a Navy 134 or Army
> PL-65 they'd like to part with?
>
> I'd prefer the 134 as this is for an
> RU-19 project, but the PL-65 will
> do fine.
>
> This is the 6 contact connector for
> the cable from the dynamotor to junction
> box.
>
> Thanks
>
> Jack Antonio
> WA7DIA
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201113/12d9af6c/attachment.html>

From Kargo_cult at msn.com  Fri Nov 13 22:29:10 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sat, 14 Nov 2020 03:29:10 +0000
Subject: [Milsurplus] Identify this tuning capacitor ?
Message-ID: <MWHPR22MB026918F0A71E3547AEA10ADFE4E50@MWHPR22MB0269.namprd22.prod.outlook.com>

What was this tuning cap intended for? Looks new.

I can only guess R-808 or SRR-13.

Possibly only use now in antenna tuner?

thanks, Hue Miller



[A picture containing indoor, sitting, suitcase, cat  Description automatically generated]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/0567eb5f/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 99004 bytes
Desc: image001.jpg
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/0567eb5f/attachment-0002.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 37713 bytes
Desc: image002.jpg
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/0567eb5f/attachment-0003.jpg>

From mark.k3msb at gmail.com  Sat Nov 14 08:46:32 2020
From: mark.k3msb at gmail.com (Mark K3MSB)
Date: Sat, 14 Nov 2020 08:46:32 -0500
Subject: [Milsurplus] WTB: ARB Pilot's Control Box
Message-ID: <CABdVoaCPKRZjZM5DJhYipYHdoGMSyTkQ6hrX4BJ-zbA8+rspHw@mail.gmail.com>

Hi All

Next year I'm planning on restoring my ARB receiver.  I have all the
components except the Pilot's control box.    If anyone has one they'd care
to part with, please contact me.

73 Mark K3MSB
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/17775cf5/attachment.html>

From mark.k3msb at gmail.com  Sat Nov 14 09:10:19 2020
From: mark.k3msb at gmail.com (Mark K3MSB)
Date: Sat, 14 Nov 2020 09:10:19 -0500
Subject: [Milsurplus] SCR-AR-183 Parts Needed
Message-ID: <CABdVoaCwbRMqsxYnQKTWj9iMR5cVu7dzTHztfQ-kJMs5xwqidw@mail.gmail.com>

Hello All

Next year I plan on restoring my SCR-AR-183 system.

I need the junction box.   The correct one is the TM-AH-172.   If anyone
has one that they'd like to part with, please let me know.     More
realistically,  I'm going to have to build a junction box.   I have no
clear pictures of the TM-AH-172.   The only pictures I've found on the web
are darkened scans of manual photos and provide little details.   Might
anyone have a clear picture?

If I go the home-brew route I would not use the correct jacks (cost
concerns), but I'd like to be close to the correct dimensions and jack
layout.   I've also read that junction boxes came with the airframe, and
that many times they were built after the fact,  so perhaps a home brew one
is not too far from reality. Comments?

I have an unused RU-3 Junction Box I'd be willing to use as (part of a
trade) for a TM-AH-172.   It has the yellow M in a yellow circle.

Also,  I'm looking for a BC-AR-198 relay.   I have a BC-AR-408 relay which
is 28V (and the SC-AR-183 is a 14V system).    I was planning on replacing
the relay in the 408,  but would prefer to swap for a BC-AR-198 (or just
purchase).

Finally,  my BC-AR-229 receiver has had the original front panel connector
replaced with a Cinch Jones connector.   I'm looking for the original
connector.

73 Mark K3MSB
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/d275037a/attachment.html>

From kk5f at earthlink.net  Sat Nov 14 13:27:38 2020
From: kk5f at earthlink.net (Mike Morrow)
Date: Sat, 14 Nov 2020 13:27:38 -0500 (EST)
Subject: [Milsurplus] [ARC5] SCR-AR-183 Parts Needed
Message-ID: <1652361813.1778.1605378459200@wamui-milano.atl.sa.earthlink.net>

An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/77f5b569/attachment.html>

From arc5 at ix.netcom.com  Sat Nov 14 14:16:45 2020
From: arc5 at ix.netcom.com (David Stinson)
Date: Sat, 14 Nov 2020 13:16:45 -0600
Subject: [Milsurplus] Stuck WWII Connectors.
Message-ID: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>

Most of us have heard this before,
but for those who have not:
I was hunting through WWII Navy
connectors this morning.? All the ones
I picked were stuck fast in their shells.
The Bakelite will absorb moisture over
time, swell and stick in the shells.
One can destroy the connector
attempting to remove the inserts
at this point.

https://photos.app.goo.gl/NDM2e22j3SpQiRQZ9

I preheated my oven to 250 Degs F.
Needs to be higher than boiling water (220 Degs F.)
Left them in the over for 1 hour.
Then pulled them out and let them cool
completely- about another hour.

All but one are now completely loose in
their shells, with the one Army connector
being slightly sticky and needing a bump
to get it out.

https://photos.app.goo.gl/YGJAj57GY527G26N6

In case someone hasn't heard of this.
73 Dave AB5S


-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


From arc5 at ix.netcom.com  Sat Nov 14 17:24:36 2020
From: arc5 at ix.netcom.com (David Stinson)
Date: Sat, 14 Nov 2020 16:24:36 -0600
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>
	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
Message-ID: <6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>

I forgot to note that sometimes it
takes more than one treatment.

-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


From hwhall at compuserve.com  Sat Nov 14 18:09:23 2020
From: hwhall at compuserve.com (hwhall at compuserve.com)
Date: Sat, 14 Nov 2020 23:09:23 +0000 (UTC)
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>
	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
	<6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>
Message-ID: <638078428.5519483.1605395363395@mail.yahoo.com>

I'd not be surprised that it would take time for moisture to escape from a solid like bakelite even when warmed. Personally, I'd be afraid of 220F+ temps on the chance that steam escaping quickly (or trying to) could do some damage. But if others haven't seen any such occurrence maybe that's just a touch of over-thinking it.

WayneWB4OGM

-----Original Message-----
From: David Stinson <arc5 at ix.netcom.com>
To: milsurplus at mailman <milsurplus at mailman.qth.net>
Cc: ARC-5 <arc5 at mailman.qth.net>
Sent: Sat, Nov 14, 2020 3:24 pm
Subject: Re: [ARC5] Stuck WWII Connectors.

I forgot to note that sometimes it
takes more than one treatment.

-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

______________________________________________________________
ARC5 mailing list
Home: http://mailman.qth.net/mailman/listinfo/arc5
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:ARC5 at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: https://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201114/310e7197/attachment.html>

From smithab11 at comcast.net  Sun Nov 15 15:06:34 2020
From: smithab11 at comcast.net (B. Smith)
Date: Sun, 15 Nov 2020 15:06:34 -0500
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <638078428.5519483.1605395363395@mail.yahoo.com>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>
	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
	<6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>
	<638078428.5519483.1605395363395@mail.yahoo.com>
Message-ID: <6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>

 ?Kano "KROIL" oil penetrate will unstick any thing. A "little dab will 
do you".
k4che

On 11/14/2020 6:09 PM, hwhall at compuserve.com wrote:
> I'd not be surprised that it would take time for moisture to escape 
> from a solid like bakelite even when warmed. Personally, I'd be afraid 
> of 220F+ temps on the chance that steam escaping quickly (or trying 
> to) could do some damage. But if others haven't seen any such 
> occurrence maybe that's just a touch of over-thinking it.
>
> Wayne
> WB4OGM
>
> -----Original Message-----
> From: David Stinson <arc5 at ix.netcom.com>
> To: milsurplus at mailman <milsurplus at mailman.qth.net>
> Cc: ARC-5 <arc5 at mailman.qth.net>
> Sent: Sat, Nov 14, 2020 3:24 pm
> Subject: Re: [ARC5] Stuck WWII Connectors.
>
> I forgot to note that sometimes it
> takes more than one treatment.
>
>
> -- 
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net <mailto:ARC5 at mailman.qth.net>
>
> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
> Please help support this email list: https://www.qsl.net/donate.html
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html


From hwhall at compuserve.com  Sun Nov 15 15:17:05 2020
From: hwhall at compuserve.com (hwhall at compuserve.com)
Date: Sun, 15 Nov 2020 20:17:05 +0000 (UTC)
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>
	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
	<6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>
	<638078428.5519483.1605395363395@mail.yahoo.com>
	<6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
Message-ID: <1039556629.5648672.1605471425161@mail.yahoo.com>

Seems to me that soaking an already swollen & stuck plug insert will only make the swelling worse & possibly harder to "undo" than baking out mere water.

WayneWB4OGM

-----Original Message-----
From: B. Smith <smithab11 at comcast.net>
To: milsurplus at mailman.qth.net <milsurplus at mailman.qth.net>
Cc: arc5 at mailman.qth.net <arc5 at mailman.qth.net>
Sent: Sun, Nov 15, 2020 1:06 pm
Subject: Re: [Milsurplus] [ARC5] Stuck WWII Connectors.

 ?Kano "KROIL" oil penetrate will unstick any thing. A "little dab will 
do you".
k4che

On 11/14/2020 6:09 PM, hwhall at compuserve.com wrote:
> I'd not be surprised that it would take time for moisture to escape 
> from a solid like bakelite even when warmed. Personally, I'd be afraid 
> of 220F+ temps on the chance that steam escaping quickly (or trying 
> to) could do some damage. But if others haven't seen any such 
> occurrence maybe that's just a touch of over-thinking it.
>
> Wayne
> WB4OGM
>
> -----Original Message-----
> From: David Stinson <arc5 at ix.netcom.com>
> To: milsurplus at mailman <milsurplus at mailman.qth.net>
> Cc: ARC-5 <arc5 at mailman.qth.net>
> Sent: Sat, Nov 14, 2020 3:24 pm
> Subject: Re: [ARC5] Stuck WWII Connectors.
>
> I forgot to note that sometimes it
> takes more than one treatment.
>
>
> -- 
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net <mailto:ARC5 at mailman.qth.net>
>
> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
> Please help support this email list: https://www.qsl.net/donate.html
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201115/bfe35ebb/attachment-0001.html>

From Kargo_cult at msn.com  Sun Nov 15 18:15:16 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sun, 15 Nov 2020 23:15:16 +0000
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>
	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
	<6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>
	<638078428.5519483.1605395363395@mail.yahoo.com>
	<6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
Message-ID: <MWHPR22MB0269B1041125176A59519A44E4E40@MWHPR22MB0269.namprd22.prod.outlook.com>

Yeah, but if the insert has increased in size, seems like the right approach is to decrease it in size, if you can. 
Which means "baking", not lubing.
-Hue

>Kano "KROIL" oil penetrate will unstick any thing. A "little dab will do you".
k4che


From w2hx at w2hx.com  Sun Nov 15 18:43:23 2020
From: w2hx at w2hx.com (W2HX)
Date: Sun, 15 Nov 2020 23:43:23 +0000
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>
	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>
	<6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>
	<638078428.5519483.1605395363395@mail.yahoo.com>
	<6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
Message-ID: <fa2d7380ebe24e059c5f81f0b7fa743d@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>

Graphited or non-graphited? Kano Penephite, Kano Aerokroil or SiliKroil?

Eugene


-----Original Message-----
From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of B. Smith
Sent: Sunday, November 15, 2020 3:07 PM
To: milsurplus at mailman.qth.net
Cc: arc5 at mailman.qth.net
Subject: Re: [Milsurplus] [ARC5] Stuck WWII Connectors.

 ?Kano "KROIL" oil penetrate will unstick any thing. A "little dab will do you".
k4che

On 11/14/2020 6:09 PM, hwhall at compuserve.com wrote:
> I'd not be surprised that it would take time for moisture to escape 
> from a solid like bakelite even when warmed. Personally, I'd be afraid 
> of 220F+ temps on the chance that steam escaping quickly (or trying
> to) could do some damage. But if others haven't seen any such 
> occurrence maybe that's just a touch of over-thinking it.
>
> Wayne
> WB4OGM
>
> -----Original Message-----
> From: David Stinson <arc5 at ix.netcom.com>
> To: milsurplus at mailman <milsurplus at mailman.qth.net>
> Cc: ARC-5 <arc5 at mailman.qth.net>
> Sent: Sat, Nov 14, 2020 3:24 pm
> Subject: Re: [ARC5] Stuck WWII Connectors.
>
> I forgot to note that sometimes it
> takes more than one treatment.
>
>
> --
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net <mailto:ARC5 at mailman.qth.net>
>
> This list hosted by: http://www.qsl.net <http://www.qsl.net/> Please 
> help support this email list: https://www.qsl.net/donate.html
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net Please help support this email 
> list: http://www.qsl.net/donate.html

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

From wa5cab at cs.com  Mon Nov 16 02:54:08 2020
From: wa5cab at cs.com (Robert Downs)
Date: Mon, 16 Nov 2020 01:54:08 -0600
Subject: [Milsurplus] [ARC5] Stuck WWII Connectors.
In-Reply-To: <fa2d7380ebe24e059c5f81f0b7fa743d@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>
References: <8660d457-6323-6ff4-5c97-6d509842ad48@ix.netcom.com>	<CAFeDsnmJc0RBhm-FBSCWePE8UkOqcKmeQNdHNfGVHtiOc6Ks4w@mail.gmail.com>	<6033bde2-0c35-8254-7887-a70e1d6be7de@ix.netcom.com>	<638078428.5519483.1605395363395@mail.yahoo.com>	<6bee4643-6034-d9ab-e1bc-1b6abf265a4d@comcast.net>
	<fa2d7380ebe24e059c5f81f0b7fa743d@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>
Message-ID: <000001d6bbed$aab76fc0$00264f40$@com>

As has been said or indicated throughout this thread, the black phenolic insert is not "stuck" in the same sense that for example a screw that has been in a nut for decades may be stuck.  The cast phenolic absorbs moisture over decades and swells so that the original light push fit has become an interference fit.  No amount of Kroil, graphite, or any other penetrant or lubricant will help.  It may in fact make matters worse.  Removing the retaining screw and baking in a 200 degree oven for one to three hours is AFAIK the simplest solution.  The only other method that might work would be a vacuum chamber.  But it would probably take months or years instead of hours.

The only other method that works (which I used to do all the time before Dave figured out the oven fix) is to make a proper receiver and removal tool and press the insert out of the sleeve with an arbor press.  Then mount each insert in a lathe and reduce the diameter by 0.002 to 0.004".  This method does work but takes time for each one and requires that you have a good lathe with near zero runout and good reflexes.  And in 30 or 40 years, you would probably have to do it again.

Robert Downs

-----Original Message-----
From: milsurplus-bounces at mailman.qth.net [mailto:milsurplus-bounces at mailman.qth.net] On Behalf Of W2HX
Sent: Sunday, November 15, 2020 17:43
To: B. Smith; milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] [ARC5] Stuck WWII Connectors.

Graphited or non-graphited? Kano Penephite, Kano Aerokroil or SiliKroil?

Eugene




From RAFANTINI at salisbury.edu  Mon Nov 16 16:11:20 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Mon, 16 Nov 2020 21:11:20 +0000
Subject: [Milsurplus] 10th anniversary M&S Net Video
Message-ID: <BY5PR02MB67550BDB40074E1180454CCFB8E30@BY5PR02MB6755.namprd02.prod.outlook.com>

I set up a flip camera and recorder some highlights of the 10th anniversary Moose & Squirrel Clandestine Cold War Radio Net last Saturday the 14th of November, items of note were that our fearless leader Al N3FRQ was pressed into service with his PRC-47 as net control, I drove the mutt out into a very wet back yard and set up running the GRC-106 along with the video camera and altogether there were nine stations on the net that were all running the AN/PRC-47 transceiver. Perhaps a record for the most forty sevens on the air at one time in one net? Think the total for the net was just under thirty stations with other notable radios including Sunair, KWM-2A and some commercial stuff.

You can see the video at:

https://www.youtube.com/watch?v=BDWuuc38wQA

Sorry for the wind noise but it was a bit windy that day.

For those who don't know the Moose & Squirrel Net is held every Tuesday, Thursday and Saturday at noon EST on 5357 USB and presents a great opportunity to drag out the Cold War or Vietnam era radios and put them back on the air.

Ray F/KA3EKH

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201116/8f89d32b/attachment-0001.html>

From ramcam at magma.ca  Mon Nov 16 16:40:24 2020
From: ramcam at magma.ca (Ralph)
Date: Mon, 16 Nov 2020 16:40:24 -0500
Subject: [Milsurplus] FT-501
Message-ID: <d5e2cd70-7d22-8b45-6357-e51a372d19c2@magma.ca>

Anyone have an FT-501 battery adaptor for the BC-611, surplus to their 
needs? Pls email. Thanks

Ralph, VE3BBM


From ramcam at magma.ca  Mon Nov 16 16:41:47 2020
From: ramcam at magma.ca (Ralph)
Date: Mon, 16 Nov 2020 16:41:47 -0500
Subject: [Milsurplus] RT-19D purpose
Message-ID: <569f58ea-f395-c627-3736-0bd43766a320@magma.ca>

What was the purpose of the R-19D FM broadcast receiver?

Ralph VE3BBM


From n4fs at eozinc.com  Mon Nov 16 16:48:19 2020
From: n4fs at eozinc.com (Mike Feher)
Date: Mon, 16 Nov 2020 16:48:19 -0500
Subject: [Milsurplus] FT-501
In-Reply-To: <d5e2cd70-7d22-8b45-6357-e51a372d19c2@magma.ca>
References: <d5e2cd70-7d22-8b45-6357-e51a372d19c2@magma.ca>
Message-ID: <013701d6bc62$33074660$9915d320$@eozinc.com>

I have a couple Ralph. It may take a while to dig out. Hope you have been
well. 73 - Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115

-----Original Message-----
From: milsurplus-bounces at mailman.qth.net
<milsurplus-bounces at mailman.qth.net> On Behalf Of Ralph
Sent: Monday, November 16, 2020 4:40 PM
To: milsurplus at mailman.qth.net
Subject: [Milsurplus] FT-501

Anyone have an FT-501 battery adaptor for the BC-611, surplus to their
needs? Pls email. Thanks

Ralph, VE3BBM

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


From gfsmith at cox.net  Mon Nov 16 17:06:47 2020
From: gfsmith at cox.net (Gordon Smith)
Date: Mon, 16 Nov 2020 14:06:47 -0800
Subject: [Milsurplus] RT-19D purpose
In-Reply-To: <569f58ea-f395-c627-3736-0bd43766a320@magma.ca>
References: <569f58ea-f395-c627-3736-0bd43766a320@magma.ca>
Message-ID: <mailman.507.1605564417.3112.milsurplus@mailman.qth.net>

Hi Ralph,
Per this thread ( 
https://www.antiqueradios.com/forums/viewtopic.php?p=931122 ) the 
R-19/TRC-1 was "used in transportable relay stations for telephone 
and teletype communication "

73, Gordon KJ6IKT

At 01:41 PM 11/16/2020, Ralph wrote:
>What was the purpose of the R-19D FM broadcast receiver?
>
>Ralph VE3BBM
>
>______________________________________________________________
>Milsurplus mailing list
>Home: http://mailman.qth.net/mailman/listinfo/milsurplus
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:Milsurplus at mailman.qth.net
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html


From kk5f at earthlink.net  Mon Nov 16 18:21:29 2020
From: kk5f at earthlink.net (Mike Morrow)
Date: Mon, 16 Nov 2020 17:21:29 -0600 (GMT-06:00)
Subject: [Milsurplus] RT-19D purpose
Message-ID: <658988431.7661.1605568889331@wamui-gaston.atl.sa.earthlink.net>

FWIW, your subject line states RT-19, which is the four-channel VHF-AM receiver-transmitter RT-19/ARC-4.

There is a depiction of the R-19 and T-14 in the AN/TRC-1, plus manuals, found here:

  https://www.radionerds.com/index.php/AN~TRC-1

This has never been a set popular with hams.

Mike / KK5F

-----Original Message-----
>From: Ralph <ramcam at magma.ca>
>Sent: Nov 16, 2020 3:41 PM
>To: milsurplus at mailman.qth.net
>Subject: [Milsurplus] RT-19D purpose
>
>What was the purpose of the R-19D FM broadcast receiver?
>
>Ralph VE3BBM

From r390a.urr at gmail.com  Tue Nov 17 10:40:39 2020
From: r390a.urr at gmail.com (Dave Merrill)
Date: Tue, 17 Nov 2020 09:40:39 -0600
Subject: [Milsurplus] RT-19D purpose
In-Reply-To: <658988431.7661.1605568889331@wamui-gaston.atl.sa.earthlink.net>
References: <658988431.7661.1605568889331@wamui-gaston.atl.sa.earthlink.net>
Message-ID: <CAGRTi8UNh9=VHEezj1pSYLH1O9aSC25b=WAdBnO-RCW+1a3NOw@mail.gmail.com>

And neither was it's successor, the AN/TRC-24.

Dave

On Mon, Nov 16, 2020, 5:21 PM Mike Morrow <kk5f at earthlink.net> wrote:

> FWIW, your subject line states RT-19, which is the four-channel VHF-AM
> receiver-transmitter RT-19/ARC-4.
>
> There is a depiction of the R-19 and T-14 in the AN/TRC-1, plus manuals,
> found here:
>
>   https://www.radionerds.com/index.php/AN~TRC-1
>
> This has never been a set popular with hams.
>
> Mike / KK5F
>
> -----Original Message-----
> >From: Ralph <ramcam at magma.ca>
> >Sent: Nov 16, 2020 3:41 PM
> >To: milsurplus at mailman.qth.net
> >Subject: [Milsurplus] RT-19D purpose
> >
> >What was the purpose of the R-19D FM broadcast receiver?
> >
> >Ralph VE3BBM
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201117/4763e680/attachment-0001.html>

From scr287 at att.net  Wed Nov 18 10:15:22 2020
From: scr287 at att.net (Jack Antonio)
Date: Wed, 18 Nov 2020 10:15:22 -0500
Subject: [Milsurplus] Sort of off topic
References: <60ec1767-4629-7e07-bfe1-6469e12686d6.ref@att.net>
Message-ID: <60ec1767-4629-7e07-bfe1-6469e12686d6@att.net>

Hi All,

First, my wife has a small business here in Warner Robins,
GA. The city was going to have a 75th anniversary of the
end of WWII celebration. As a part of that, my wife did
a WWII theme in her front window. Posters, and I supplied
a BC-342 and a couple of EE-8s. (The celebration and dance
were, of course, cancelled).

One of her customers saw that, and said he had something
to give me that I might be interested in.

So I am now the proud owner of an AMES 1945 folding
shovel.

Gotta go dig some foxholes.

Jack Antonio
WA7DIA

From wrcromwell at gmail.com  Wed Nov 18 10:50:09 2020
From: wrcromwell at gmail.com (Bill Cromwell)
Date: Wed, 18 Nov 2020 10:50:09 -0500
Subject: [Milsurplus] Sort of off topic
In-Reply-To: <60ec1767-4629-7e07-bfe1-6469e12686d6@att.net>
References: <60ec1767-4629-7e07-bfe1-6469e12686d6.ref@att.net>
	<60ec1767-4629-7e07-bfe1-6469e12686d6@att.net>
Message-ID: <9f51fd06-7f43-cb6f-9d46-250960f99e0b@gmail.com>

Hi,

Use that shovel to make a slot in the ground for your radials and buried 
feedlines:)

73,

Bill  KU8H

bark less - wag more

On 11/18/20 10:15 AM, Jack Antonio wrote:
> Hi All,
> 
> First, my wife has a small business here in Warner Robins,
> GA. The city was going to have a 75th anniversary of the
> end of WWII celebration. As a part of that, my wife did
> a WWII theme in her front window. Posters, and I supplied
> a BC-342 and a couple of EE-8s. (The celebration and dance
> were, of course, cancelled).
> 
> One of her customers saw that, and said he had something
> to give me that I might be interested in.
> 
> So I am now the proud owner of an AMES 1945 folding
> shovel.
> 
> Gotta go dig some foxholes.
> 
> Jack Antonio
> WA7DIA
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> 

From Paul.Thekan at cpii.com  Thu Nov 19 09:44:50 2020
From: Paul.Thekan at cpii.com (Thekan, Paul)
Date: Thu, 19 Nov 2020 14:44:50 +0000
Subject: [Milsurplus] FS: KA6PGN SK radios
In-Reply-To: <DM2P110MB0169FC47235C0F815107BECE9DE00@DM2P110MB0169.NAMP110.PROD.OUTLOOK.COM>
References: <DM2P110MB0169A38C58564761D52591AD9DE00@DM2P110MB0169.NAMP110.PROD.OUTLOOK.COM>,
	<DM2P110MB0169FC47235C0F815107BECE9DE00@DM2P110MB0169.NAMP110.PROD.OUTLOOK.COM>
Message-ID: <DM2P110MB0169FD114680847D1609E6A09DE00@DM2P110MB0169.NAMP110.PROD.OUTLOOK.COM>





________________________________




All

 Chuck N7UVZ  asked me to post some of Mikes radios for sale that he is going through at Mikes place in Thermal.
These are for pick up only in Thermal Calif. You can contact Chuck at     j-mcclurg at sbcglobal.net

 Chuck said he will be home Saturday to answer any emails.
**I'm only the messenger and am not involved in this operation.**

This is but a few of the items available and for you to make an offer on

1 ea NIB RT 77 GRC-9 radio

2ea NIB GN 58 w/handcranks

1ea NOS PE 162 gas gen for GRC 9

1ea NOS CW-206 canvas bag that has gen legs , ant base, whip ant , spares box..etc all for the GRC-9

2 ea DY-88 dynamotors for GRC 9

1 ea NOS PE 327 AC pwr supply ( heavy) for GRC 9

1 ea of RT66 -67 68 radios

Assortment of the Tank radios xmtrs and rcvrs . Not sure all whats there but like the BC 683 684 and 603 and 604.
And one known single rcvr shock mount.

 Again please contact Chuck N7UVZ with any inquires on these items or what else might be available.

Paul
N6FEG



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201119/52d32692/attachment.html>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: ATT00001.txt
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201119/52d32692/attachment.txt>

From RAFANTINI at salisbury.edu  Thu Nov 19 10:59:12 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Thu, 19 Nov 2020 15:59:12 +0000
Subject: [Milsurplus] Able Archer 83 enent
Message-ID: <BY5PR02MB6755365E834EBA1EEFA7C821B8E00@BY5PR02MB6755.namprd02.prod.outlook.com>

The Able Archer 83 event will still be happening this weekend, with all this Covid stuff going on right now do not expect to see many visitors at the site and don't see any opportunity for doing anything like local field exercises so long story short figure that we will be just setting up the station and the mutt at the site.
We will be operating from Fort Miles located at Cape Henlopen State Park in Delaware, the one time Cold War home of NAVFAC Lewes.

The event starts at noon local but have authorization to use the special event call W3A for the entire weekend so intend to check in to both MMRCG and Moose & Squirrel Nets that morning using the W3A call. In addition to voice operations intend to be operating the GRC-106 in FSK running 60 WPM 850 Hz shift, was thinking of working around 7080 or maybe 7087 but am open for suggestions.

We will have equipment for most HF/SSB and CW along with radios for 51.0 FM that I will monitor, intend to be on-site all-day Saturday and up till noon on Sunday.
Would like to try close in RTTY on maybe 20 meters or 17 meters (18.10) during daytime using just vertical antenna on mutt, the vertical preforms best on the higher bands.
If anyone would like to try something at any particular time please let me know and we can set up a schedule.

Additional information about the event can be seen at:

https://sites.google.com/site/ablearcher1983w3a

Ray F/KA3EKH


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201119/436e5de0/attachment-0001.html>

From robert.h.goff at gmail.com  Thu Nov 19 12:02:27 2020
From: robert.h.goff at gmail.com (Robert Goff)
Date: Thu, 19 Nov 2020 09:02:27 -0800
Subject: [Milsurplus] Chinese Type 116 Transmitter?
Message-ID: <CAF6Vb54hrFJOU+ifSbs1_dkToihTW87RwhMQqfdRDTzQW4Jabg@mail.gmail.com>

Hi
I'd like to hear from anybody with experience with the Chinese PLA
type 116 transmitter.  I think I got mine NOS from Harry at Red Star
Radio, so he probably sold at least a couple more.

As an old Russian student with no Chinese, I've got some questions!

Thanks and 73,
de Robert W7MKA

From Kargo_cult at msn.com  Thu Nov 19 17:47:34 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Thu, 19 Nov 2020 22:47:34 +0000
Subject: [Milsurplus] SE 108/10 In Norway Outdoors
Message-ID: <MWHPR22MB0269041E64E67FDFE093A7B9E4E00@MWHPR22MB0269.namprd22.prod.outlook.com>

Here is a fun video of a Norwegian ham trying out a WWII German spy - type radio in some
very scenic settings. The radio construction is what you might call 'biscuit tin style'. Not
entirely explained is that his ancillary equipment includes a storage battery and inverter
for the AC requirement of the radio. Also instead of the issue headphone he is using an
external speaker and an antenna switchbox. The radio has itself no means of switching
antennas for receive - transmit turns and the output circuit, just a tapped coil, has minimal
harmonic suppression. He says he stayed out there one night, but his pack is pretty well
taken up with the radio gear, so his buddy, the videographer, must have been carrying other
supplies.

https://www.youtube.com/watch?v=MD07aScrKv0&feature=youtu.be


The radio is a one tube transmitter using a tube similar maybe to 50C5. The receiver is
3 valves with the first doing RF amp and reflexed first audio and regenerative detector. In
the old times way of describing the circuit, 1-V-2.

When you see this fellow's radio room you get the idea that he's an all-in fanatic for WWII
German equipment.

I have the same model radio, obtained from a veteran who took it from the team he
investigated. In that case, near the end of the war, the radio's owners were not shot - they
were just sent into the general POW pen.
-Hue Miller
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201119/5be1fbd8/attachment.html>

From w2hx at w2hx.com  Thu Nov 19 18:17:54 2020
From: w2hx at w2hx.com (W2HX)
Date: Thu, 19 Nov 2020 23:17:54 +0000
Subject: [Milsurplus] SE 108/10 In Norway Outdoors
In-Reply-To: <MWHPR22MB0269041E64E67FDFE093A7B9E4E00@MWHPR22MB0269.namprd22.prod.outlook.com>
References: <MWHPR22MB0269041E64E67FDFE093A7B9E4E00@MWHPR22MB0269.namprd22.prod.outlook.com>
Message-ID: <0e02125f17f940c090e8642d16e1608f@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>

Sounds like there is a code practice oscillator responding to him! Very good filtering and no noise (must be nice to live in a place like that)!

From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Hubert Miller
Sent: Thursday, November 19, 2020 5:48 PM
To: milsurplus at mailman.qth.net; Army-Radios <main+owner at Army-Radios.groups.io>
Subject: [Milsurplus] SE 108/10 In Norway Outdoors

Here is a fun video of a Norwegian ham trying out a WWII German spy - type radio in some
very scenic settings. The radio construction is what you might call 'biscuit tin style'. Not
entirely explained is that his ancillary equipment includes a storage battery and inverter
for the AC requirement of the radio. Also instead of the issue headphone he is using an
external speaker and an antenna switchbox. The radio has itself no means of switching
antennas for receive - transmit turns and the output circuit, just a tapped coil, has minimal
harmonic suppression. He says he stayed out there one night, but his pack is pretty well
taken up with the radio gear, so his buddy, the videographer, must have been carrying other
supplies.

https://www.youtube.com/watch?v=MD07aScrKv0&feature=youtu.be


The radio is a one tube transmitter using a tube similar maybe to 50C5. The receiver is
3 valves with the first doing RF amp and reflexed first audio and regenerative detector. In
the old times way of describing the circuit, 1-V-2.

When you see this fellow's radio room you get the idea that he's an all-in fanatic for WWII
German equipment.

I have the same model radio, obtained from a veteran who took it from the team he
investigated. In that case, near the end of the war, the radio's owners were not shot - they
were just sent into the general POW pen.
-Hue Miller

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201119/fa623040/attachment-0001.html>

From Kargo_cult at msn.com  Thu Nov 19 20:59:46 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Fri, 20 Nov 2020 01:59:46 +0000
Subject: [Milsurplus] Forest Service SPF radio detail
Message-ID: <MWHPR22MB02698709418160C7B6163CE1E4FF0@MWHPR22MB0269.namprd22.prod.outlook.com>

I was looking at WB6NVH's website pages on the Forest Service type SPF radio, and he gives the likely 
output impedance of the transmitter as dealing with 100 ohm load. But - the SPF was intended to be
used with either 1/2 wave endfed, or a Windom. I have just now looked at Windom antenna listings on
the net, and I mean SINGLE-wire feed, not coax, but it seems every article is shy about giving the Z of
the Windom antenna. I read that the original idea was to tap at guesstimated 600 ohm load. But I notice
the commercial OCF antennas now offered have a 1:4 balun. I assume this is ohms ratio, not winding ratio?
Otherwise the coax to antenna ratio would give 800 ohm antenna. If it's ohms ratio, then this assumes the
antenna about 200 ohms. I don't know the exact impedance of an end fed 1/2 wave, and maybe no one
else does either, but I assume around 1000 - 2000 ohm. So for the SPF article I mentioned above, I would
instead state that the SPF is intended for antenna impedance of 600 to 2000 ohm. 
What say?
-Hue Miller 

From kgordon2006 at frontier.com  Thu Nov 19 22:48:24 2020
From: kgordon2006 at frontier.com (Kenneth G. Gordon)
Date: Thu, 19 Nov 2020 19:48:24 -0800
Subject: [Milsurplus] Forest Service SPF radio detail
In-Reply-To: <MWHPR22MB02698709418160C7B6163CE1E4FF0@MWHPR22MB0269.namprd22.prod.outlook.com>
References: <MWHPR22MB02698709418160C7B6163CE1E4FF0@MWHPR22MB0269.namprd22.prod.outlook.com>
Message-ID: <5FB73C88.27528.29BAA1E@kgordon2006.frontier.com>

On 20 Nov 2020 at 1:59, Hubert Miller wrote:

> I was looking at WB6NVH's website pages on the Forest Service type SPF radio, and he gives the likely 
> output impedance of the transmitter as dealing with 100 ohm load. But - the SPF was intended to be
> used with either 1/2 wave endfed, or a Windom. I have just now looked at Windom antenna listings on
> the net, and I mean SINGLE-wire feed, not coax, but it seems every article is shy about giving the Z of
> the Windom antenna. I read that the original idea was to tap at guesstimated 600 ohm load. But I notice
> the commercial OCF antennas now offered have a 1:4 balun. I assume this is ohms ratio, not winding ratio?
> Otherwise the coax to antenna ratio would give 800 ohm antenna. If it's ohms ratio, then this assumes the
> antenna about 200 ohms. I don't know the exact impedance of an end fed 1/2 wave, and maybe no one
> else does either, but I assume around 1000 - 2000 ohm. So for the SPF article I mentioned above, I would
> instead state that the SPF is intended for antenna impedance of 600 to 2000 ohm. 
> What say?

One of my first antennas was an off-center-fed Windom, single-wire feed. My transmitter was 
a Heathkit DX-35, which loaded it just fine.

I suspect the impedance is 200 ohms, not 600, since as I recall it, the DX-35 wouldn't load 
into 600 ohms.

Ken W7EKB

From scr287 at att.net  Fri Nov 20 10:52:49 2020
From: scr287 at att.net (Jack Antonio)
Date: Fri, 20 Nov 2020 10:52:49 -0500
Subject: [Milsurplus] RU-16 GT-11 parts units
References: <5b67b381-2e36-fb1c-ca6f-b5ca5bdf6ec9.ref@att.net>
Message-ID: <5b67b381-2e36-fb1c-ca6f-b5ca5bdf6ec9@att.net>

Hello all

In rounding up other stuff, I came across
an RU-16 receiver, and GF-11 transmitter.

These are parts units. They probably
could be made to function, but are
a bit to drilled on to be restorable.

No coil sets or tubes, and the
receiver is missing its front
panel connector.

Anyone want them for postage?

Trying to reduce the piles around here.

Jack Antonio
WA7DIA

From scr287 at att.net  Fri Nov 20 13:27:33 2020
From: scr287 at att.net (Jack Antonio)
Date: Fri, 20 Nov 2020 13:27:33 -0500
Subject: [Milsurplus] RU GF gear spoken for
References: <6695736e-c6af-3603-a2fb-55fee2d55182.ref@att.net>
Message-ID: <6695736e-c6af-3603-a2fb-55fee2d55182@att.net>

The RU and GF are taken.

Thanks for the replies

Jack Antonio
WA7DiA

From RAFANTINI at salisbury.edu  Sat Nov 21 06:55:39 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Sat, 21 Nov 2020 11:55:39 +0000
Subject: [Milsurplus] todays activity
Message-ID: <BY5PR02MB6755537DB3A5627F6FEE78BFB8FE0@BY5PR02MB6755.namprd02.prod.outlook.com>

intend to be on both MMRCG 7.296 and M7S Net on 5.357 using special event call W3A operating from Fort Miles as part of AA83 event, also will be operating RTTY 60 WPM at 850 shift starting two (1400 hours) local on 7.080 or 7.087

Ray F/KA3EKH
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201121/096059ca/attachment-0001.html>

From k2cby at optonline.net  Sat Nov 21 10:51:44 2020
From: k2cby at optonline.net (k2cby at optonline.net)
Date: Sat, 21 Nov 2020 10:51:44 -0500
Subject: [Milsurplus] Forest Service SPF radio detail  (Windom)
Message-ID: <033c01d6c01e$370d03c0$a5270b40$@optonline.net>

When I started out in this game some 60 years ago the 2-wire-fed Windom was
fairly common among operators who wanted multi-band operation on a budget.
The two wire feedlines in those days were 300-Ohm television twin-lead (or
300 Ohm open wire if you could find it) , and they were coupled to the
transmitter with a Heathkit 75 Ohm to 300 Ohm balun coil and a length of
RG-11 coax. This leads me to believe that the characteristic of the Windom
antenna was somewhere around 300 Ohms. That was my Novice setup running a
Heathkit DX-40.

Single wire feed would seem to be another matter entirely because it works
against ground. As such, the actual impedance at the transmitter end not
only depends on the antenna impedance but also on the impedance of the
ground connection - i.e., length, number and size of the counterpoise
wire(s) as well as the integrity of the connections. In other words, it's
anybody's guess! 

 

Miles B. Anderson, K2CBY
16 Round Pond Lane
Sag Harbor, New York 11963-3821
Phone: (631) 725-4400
FAX: (631) 725-2223

e-mail: k2cby at optimum.net

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201121/1b827f97/attachment.html>

From Kargo_cult at msn.com  Sat Nov 21 15:24:29 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sat, 21 Nov 2020 20:24:29 +0000
Subject: [Milsurplus] Forest Service SPF radio detail  (Windom)
In-Reply-To: <033c01d6c01e$370d03c0$a5270b40$@optonline.net>
References: <033c01d6c01e$370d03c0$a5270b40$@optonline.net>
Message-ID: <BN6PR22MB025837B36DD253ACB95B11E0E4FE0@BN6PR22MB0258.namprd22.prod.outlook.com>

That seems like a good point. But then, my question assumes "perfect ground". I would guess the high impedance antennas the F.S.
used for portable equipment was to overcome to some degree less than good ground situations. 
-Hue

>When I started out in this game some 60 years ago the 2-wire-fed Windom was fairly common among operators who wanted multi-band operation on a budget. The two wire feedlines in those days were 300-Ohm television twin-lead (or 300 Ohm open wire if you could find it) , and they were coupled to the transmitter with a Heathkit 75 Ohm to 300 Ohm balun coil and a length of RG-11 coax. This leads me to believe that the characteristic of the Windom antenna was somewhere around 300 Ohms. That was my Novice setup running a Heathkit DX-40.
Single wire feed would seem to be another matter entirely because it works against ground. As such, the actual impedance at the transmitter end not only depends on the antenna impedance but also on the impedance of the ground connection - i.e., length, number and size of the counterpoise wire(s) as well as the integrity of the connections. In other words, it's anybody's guess! 

Miles B. Anderson, K2CBY



From navy.radio at gmail.com  Sat Nov 21 16:12:24 2020
From: navy.radio at gmail.com (Nick England)
Date: Sat, 21 Nov 2020 16:12:24 -0500
Subject: [Milsurplus] [MMRCG] todays activity
In-Reply-To: <BY5PR02MB6755537DB3A5627F6FEE78BFB8FE0@BY5PR02MB6755.namprd02.prod.outlook.com>
References: <BY5PR02MB6755537DB3A5627F6FEE78BFB8FE0@BY5PR02MB6755.namprd02.prod.outlook.com>
Message-ID: <CAB55hNceK13BaLD5EAGr7DfeE93o5_5+xTgWVStYWni4shmTTg@mail.gmail.com>

===========
W3A DE K4NYW
FM NAVCOMMSTA CHAPEL HILL
TO NAVRADSTA LEWES
INFO ALCON
BT
UNCLAS
1. THANKS TO RAY FOR ACTIVATING NAVFAC AND NAVRADSTA
COMMUNICATIONS AT FORT MILES FOR ABLE ARCHER 83
COMMEMORATION.
2. RAY'S GRC-106 WORKED GREAT ON RATT AND ALSO ON
THE 7296 USB NET.
3. W3A RATT WAS 100 PER CENT COPY HERE IN NC AND VICE VERSA.
WE HAD A FUN QSO.
4. I ALSO COPIED KA4RSZ AND W8OZY CALLING W3A, BUT RAY
COULDN'T HEAR THEM
5. K4NYW WAS RUNNING AN/FRT-70 XMTR AND AN//URR-74 RCVR
WITH AN/UGC-6K (MODEL 28ASR) TELETYPE.
BT
K
(8 LF)
NNNN
================
On Sat, Nov 21, 2020 at 6:55 AM Ray Fantini <RAFANTINI at salisbury.edu> wrote:
>
> intend to be on both MMRCG 7.296 and M7S Net on 5.357 using special event
call W3A operating from Fort Miles as part of AA83 event, also will be
operating RTTY 60 WPM at 850 shift starting two (1400 hours) local on 7.080
or 7.087
>
> Ray F/KA3EKH
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201121/cc0c795c/attachment.html>

From Kargo_cult at msn.com  Sat Nov 21 16:55:54 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sat, 21 Nov 2020 21:55:54 +0000
Subject: [Milsurplus] Ebay short story.
Message-ID: <BN6PR22MB02588401C090713F4B8376B6E4FE0@BN6PR22MB0258.namprd22.prod.outlook.com>

I really don't want to stir a furor of Ebay gripes and horror stories, but....i thought I'd recount 
my experience with the flag which I mentioned here about a full year ago. At that time, my
listing for a 'WWII German Balkenkreuz vehicle recognition flag' was removed as "inappropriate",
i.e. Nazi glorification. This while a search on "Balkenkreuz" found 400+ other listings with this 
name, including Balkenkreuz T-shirts for the least intelligent among us. I spoke to 2 Ebay reps
about this. The first told me "Ebay was getting to this but as there were so many listings, it would
take some time".  I waited "some time", a few months, saw no action was being taken, and again
spoke with Ebay. The young fellow told me he also saw the historical aspect and found the item
interesting, but basically, "That's just the way it is". So anyway after seeing absolutely no change
in over a year, I decided to put the flag, really a 'covering', on again. I got one personal message
of mild complaint, but this person didn't complain to Ebay. I think what happened the first time 
out, was that I refused to ship the covering to Brazil, and a person there then for revenge 
"reported" the item to Ebay as "inappropriate". This at the same time I had some Panzer radios
on Ebay, and these all bore small Armaments Ministry actual swastika stamps
Well, this time out, the flag / cover did  close successfully, and brought about $400+, which I sort 
of expected, or better said, hoped for, as I don't have a good feel for which areas of collectibles 
are down now. 

BTW, I spoke today with an Ebay rep about a different problem, and altho the rep was  fully conversant
in English, and they do really emphasize the "caring and concerned" affect, I could tell the rep is
overseas. I dutifully completed their post session feedback questionnaire, but I added this comment:
"I wish you could hire American citizens to do phone center work. 
I'm sure many ( or at least some ) Americans are smart enough to do this, are presently suffering 
underemployment, and would be happy to work from home, so a moderate wage paid would still be
worthwhile to them."

( The local seafood plant has around 40 workers here from Serbia, on 6-month contracts. They work a 
lot, 5 x 12 days, for about ( I was told ) $1450 / week, and AFAIK they get their hotel accommodations 
provided. If they work 7 x 12 ( which would kill me ), they can net $14,400 / month. When I learned about 
the foreign workers here, I thought, "Really, no Americans would work that hard? None? Or you cannot 
even get Mexican or Honduran or such guest workers, or even Venezuelans? That kind of money would go
a long long way to decreasing misery in those countries. I continue to wonder. ) 

Honestly, it seems unpatriotic for large companies doing business in the USA to have their call centers
all overseas. I suppose a lot of Americans who would work for those going wages aren't maybe the 
brightest, but this work mostly requires just looking down their script page, with referral to someone
higher up if there's more complication. Anyway, we all know who ( what ) these companies owe their
ultimate loyalty to. 
-Hue Miller 










From Captain.Kelly at outlook.com  Sun Nov 22 06:24:47 2020
From: Captain.Kelly at outlook.com (Sean Kelly)
Date: Sun, 22 Nov 2020 11:24:47 +0000
Subject: [Milsurplus] Forest Service SPF radio detail  (Windom)
In-Reply-To: <BN6PR22MB025837B36DD253ACB95B11E0E4FE0@BN6PR22MB0258.namprd22.prod.outlook.com>
References: <033c01d6c01e$370d03c0$a5270b40$@optonline.net>,
	<BN6PR22MB025837B36DD253ACB95B11E0E4FE0@BN6PR22MB0258.namprd22.prod.outlook.com>
Message-ID: <BYAPR19MB24225D8AEEB186330DF7CB83F5FD0@BYAPR19MB2422.namprd19.prod.outlook.com>

I think the salient point when using twin lead is that the tuner at the transmitter/transceiver does something to keep the reflected wave voltage and current manageable every time it returns from the antenna and that the RF energy can be reflected back from the antenna several times, each time reflected back from the tuner towards the antenna.

So, say the SWR is...3:1 and...

OK, plan "B" - because the online calculator.

Say the VSWR is  1:2.6  with the transmatch at the radio.

30 watts forward power
2 watts reverse power

The feedline deducts from the forward power, say RG-58 and 3.3 dB per 100' at 50 MHz. Out of the 15 watts that arrives at the antenna, 2 watts is reflected back to the transmatch. What I was told is that it then reflects again towards the antenna. This time 1 watt arrives (veerry quickly, packet radio fans) at the antenna and 0.9 watts enters the antenna and about 70 milliwatts is reflected back to the transmatch. At the end of each trip along the feedline, the percentage of reflected power just keeps bouncing back and forth, becoming less each time. Third trip: 40 milliwatts arrives at the antenna, 3 milliwatts is reflected and half of that arrives back at the transmatch. The 40 milliwatts arrives 5 lengths of the cable run "later" than the original 15 watts. With a velocity factor of 66% that would be ~166 meters/speed of light in free space * 1.5 =  2 micro-seconds (not enough to change the shape of the pulses of a digital mode enough to disturb its synchronization, I'm sure).

One disadvantage of ladder line is that you can't place it near metal while you are using it. But a big advantage is that the loss is so low, like 1 dB per 100' of 300 ohm twin lead:

https://www.rfcafe.com/references/electronics-world/loss-figures-300-ohm-twin-lead-january-1965-electronics-world.htm
[https://www.rfcafe.com/references/electronics-world/images/loss-300-ohm-twin-lead-electronics-world-jan-1965-1.jpg]<https://www.rfcafe.com/references/electronics-world/loss-figures-300-ohm-twin-lead-january-1965-electronics-world.htm>
Loss Figures for 300-Ohm Twin-Lead, January 1965 Electronics World - RF Cafe<https://www.rfcafe.com/references/electronics-world/loss-figures-300-ohm-twin-lead-january-1965-electronics-world.htm>
The last time I remember using 300-ohm twin-lead transmission cable for a television antenna is about 20 years ago when I lived in a fairly rural area and had a VHF/UHF aerial mounted on a 20-foot tower with a rotator.
www.rfcafe.com
So more RF energy arrives at the antenna each time, less loss so you can have a greater mismatch and transmit the same amount of the RF. It's not without limits although the Zepp Antenna is end fed by ladder line plus the Double Zepp is s wavelength long antenna center fed by ladder line so the feedpoint is a voltage node, in both cases the impedance might be 5,000 Ohms. In the case of the single Zepp, since no or very little current flows at the end/feedpoint, it's OK that the second conductor is not connected - my understanding is that the current flows back and forth in the middle, same as a half-wavelength dipole.

https://youtu.be/Js-gEZK9A-E?t=358
[https://i.ytimg.com/vi/Js-gEZK9A-E/maxresdefault.jpg]<https://youtu.be/Js-gEZK9A-E?t=358>
How a Transmatch Works<https://youtu.be/Js-gEZK9A-E?t=358>
Antenna tuners eliminate reactance and match resistance. http://www.sciencewriter.net
youtu.be
Of course, in the real world, antennas are compromises and Hugh, seems like you have almost one half of a perfect ground closeby ?

http://webclass.org/k5ijb/antennas/Windom_K4ABT-measurements.htm
Windom antenna - Webclass.org<http://webclass.org/k5ijb/antennas/Windom_K4ABT-measurements.htm>
The WINDOM Antenna G. E. "Buck" Rogers Sr - K4ABT. In September of 1949, I was tired of climbing poles and trees to move, remove, add, or change my single-band HF antenna's.
webclass.org
Sean
~~~~~
Subject: Re: [Milsurplus] Forest Service SPF radio detail (Windom)

That seems like a good point. But then, my question assumes "perfect ground". I would guess the high impedance antennas the F.S.
used for portable equipment was to overcome to some degree less than good ground situations.
-Hue

>When I started out in this game some 60 years ago the 2-wire-fed Windom
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201122/9ed31d9f/attachment-0001.html>

From Kargo_cult at msn.com  Sun Nov 22 18:54:35 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sun, 22 Nov 2020 23:54:35 +0000
Subject: [Milsurplus] Logging Yarder on M4 Tank Chassis
Message-ID: <MWHPR22MB026993DF94B64BCE10CBA7FFE4FD0@MWHPR22MB0269.namprd22.prod.outlook.com>

A month or so back I posed a question on a couple of radio forums about a Motorola portable, vacuum tube,

FM transmitter-only device, crystaled up on something like 160 MHz. There were some informative and very

interesting replies, but considering the working frequency and the set description - the set has a small microphone,

and no signal button, I think the most likely conclusion came from Geoff Fors:



"The reply with what seems the most likely answer points out that this has a U.S. Air Force contract number,

and that it may have been used with an "aircraft tow team" where someone stays on the plane being towed

and contacts the tow vehicle driver."



So, not logging industry tool.

But it was still interesting to learn about the "Talkie Tooter" and that the firm is still doing business right

here in our Northwest. Coincidently, I found in the discards at the Post Office the September 2020 issue of

"Loggers World" magazine with an article on the history of the "Tooter Talkie" as used in the logging industry.

( Do things 'happen for a reason' ? )  Besides the article, the mag had a mention of a book of humorous logging

anecdotes, which book I found on a bookseller store and bought.



Now as I file this mag in my archive, I made this below scan for general interest on the topics of 'Northwest logging'

and maybe, "WWII". It is a "Skagit SY717 yarder with Eagle Carriage, sitting on the tracks of an M4 tank from World
War 2". "CRD Logging" acquired the machine in the 1980s and the whole thing from WW2 tank chassis to yarder top

is still at work today.

-Hue Miller



[A group of people in a forest  Description automatically generated]


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201122/c9b2e884/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.jpg
Type: image/jpeg
Size: 59970 bytes
Desc: image003.jpg
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201122/c9b2e884/attachment-0001.jpg>

From w2hx at w2hx.com  Sun Nov 22 19:33:10 2020
From: w2hx at w2hx.com (W2HX)
Date: Mon, 23 Nov 2020 00:33:10 +0000
Subject: [Milsurplus] TBX Antenna Base?
Message-ID: <efe72ac83c3845f0833528415ae4a898@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>

Hi friends,
Cleaning out a drawer I found a NOS still in the paper wrapping antenna base with the number CFM-66023-A on the paper. I also have the seemingly matching ground spike with number CFM-66024. I believe this is a TBX antenna base. See here:
https://w2hx.com/ForSale/TBX/1122201915b.jpg

I have no TBX. What is it worth? $50 plus shipping?
Let me know and we can exchange details.

73 Eugene W2HX

[cid:image001.png at 01D6C105.8E3084F0]





-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201123/158d19a8/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 33123 bytes
Desc: image001.png
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201123/158d19a8/attachment-0001.png>

From RAFANTINI at salisbury.edu  Mon Nov 23 11:00:56 2020
From: RAFANTINI at salisbury.edu (Ray Fantini)
Date: Mon, 23 Nov 2020 16:00:56 +0000
Subject: [Milsurplus] Able Archer 83 AAR
Message-ID: <BY5PR02MB6755333FFA542B839B2532EAB8FC0@BY5PR02MB6755.namprd02.prod.outlook.com>

AAR Able Archer 83 on November 21/22 2020 (SHORT)
What was supposed to be achieved by this project?
Make as many contacts with as many modes as practical using Cold War era equipment at a remote location. This year we operated from Fort Miles/NAVRADSTA Lewes Delaware.
Available resources included my M151A1 mutt with AN/GRC-106A for SSB and RTTY along with VRC-46 for FM and Walt's 1 kW Sunair transceiver and assorted smaller radios and a set of period correct Autovon analog telephones.

What was actually achieved?
We received authorization to operate from the Fort Miles Complex from the Delaware State Parks Service and arrived on site Saturday morning. I set up the mutt in front of the barracks building we were using and Walt set up his Sunair station in the building.
I operated the forty-meter MMRCG Net and the Moose & Squirrel Net at noon, also ran RTTY in the afternoon conducting a half hour long QSO with K4NYW on 7080
Inside they had a couple pile ups operating both as the AA83 event and a National Parks on the Air event but later in the day they started having issues with crowded band conditions due to the ARRL QSO party that was this weekend.
We hosted maybe two hundred visitors thru the event include two boy scout troops, we had more civilian traffic at this event than any other that I have been involved with.

What aspects of the project work?

Logistics with the State Park people worked out great, they were very supportive and great host allowing us to drag out the mutt, S-250 Shelter and all the antennas and wires and the like. They also provide local power and came thru with space heaters for the night.
Despite some local interference on 60 meters did check into both regular scheduled Military Radio Nets and was also able to operate RTTY from the field using the GRC-106, and although the QSO contest did affect contact numbers think are total contacts not including the Military Nets was over one hundred.
If you are one of the stations that worked W3A on the nets I can provide information for getting a QSL from the event, just let me know if there is any interest.

What didn't work and why?

One cable came apart but we had spares on site. Radio operations were all good with the exception of the issues with the QSO Party and the local interference on sixty meters during Moose & Squirrel Net.
Largest concern may be non-radio related being the lack of any furniture in the building resulting to having to spend the night in sleeping bags on a cold concrete floor. I was lucky being I left before that and returned later on Sunday.
What would you change if given a second chance?
We are looking into making this  a all weekend event for next year. Arrive on Friday and set up, operate all day Saturday and Sunday morning with opps ending at noon on Sunday with tear down and pull out at that time.
I will also be on site entire time next year. I was late getting back Sunday morning and did not get to do any operating. Did do a couple RTTY CQ on 7087 at 1300 hours but no response.
Hope all the Covid craziness will be behind us and not have to use a mask next year. Want to also work on getting more people on site. There were only three of us this time and what was happening is that in the building we tended to get fair size groups of people and someone would have to address them.
Also want to establish some form of backpack or field radio exercise something along the lines of what we do at Gilbert for MRCA every year. The park is huge and has many places to operate from.

Ray F/KA3EKH

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201123/84fd09e4/attachment.html>

From wa5cab at cs.com  Tue Nov 24 03:42:08 2020
From: wa5cab at cs.com (Robert Downs)
Date: Tue, 24 Nov 2020 02:42:08 -0600
Subject: [Milsurplus] [MRCA] TBX Antenna Base?
In-Reply-To: <1134095887.698846.1606094064891@mail.yahoo.com>
References: <efe72ac83c3845f0833528415ae4a898@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>
	<1134095887.698846.1606094064891@mail.yahoo.com>
Message-ID: <012e01d6c23d$b2d167f0$187437d0$@com>

Yes, both parts were used with the TBX.  They were both also made by CFM.

 

I would have said $45 plus shipping for the pair.  $20 and $15.

 

Robert Downs

 

 

 

Robert Downs

 

From: mrca-bounces at mailman.qth.net [mailto:mrca-bounces at mailman.qth.net] On Behalf Of jim mullen via MRCA
Sent: Sunday, November 22, 2020 19:14
To: milsurplus at mailman.qth.net; army-radios at groups.io; Military Radio Collectors Association; W2HX
Subject: Re: [MRCA] TBX Antenna Base?

 

Great find.

 

73

 

Regards,

Jim Mullen

 

 

On Sunday, November 22, 2020, 07:35:27 PM EST, W2HX <w2hx at w2hx.com> wrote: 

 

 

Hi friends, 

Cleaning out a drawer I found a NOS still in the paper wrapping antenna base with the number CFM-66023-A on the paper. I also have the seemingly matching ground spike with number CFM-66024. I believe this is a TBX antenna base. See here:

https://w2hx.com/ForSale/TBX/1122201915b.jpg

 

I have no TBX. What is it worth? $50 plus shipping? 

Let me know and we can exchange details.

 

73 Eugene W2HX

 



 

 

 

 

 

______________________________________________________________
MRCA mailing list
Home: http://mailman.qth.net/mailman/listinfo/mrca
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:MRCA at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201124/ba8d9087/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 33123 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201124/ba8d9087/attachment-0001.png>

From n2lxm at juno.com  Thu Nov 26 14:33:58 2020
From: n2lxm at juno.com (n2lxm at juno.com)
Date: Thu, 26 Nov 2020 14:33:58 -0500
Subject: [Milsurplus] Happy Thanksgiving
Message-ID: <AABR592E5AXXWX8J@smtpout04.vgs.untd.com>

Well we are approaching the end of a very eventful and weird year. So
>From All of My Family to All of Yours. Have a Happy Thanksgiving. Stay
safe and well and pray that the coming year will be much better.


                                                    Jeff N2LXM
                                          Amateur Radio Operator
                                                      American
                                                        Patriot
                                     Proud Father of Two US Marines

____________________________________________________________
Sponsored by https://www.newser.com/?utm_source=part&utm_medium=uol&utm_campaign=rss_taglines_more

Ken Jennings Blasted for Tweet He Chose Not to Delete
http://thirdpartyoffers.juno.com/TGL3141/5fbfe09bd7858609b441ast04vuc1
After AstraZeneca's Big Vaccine Claim, Questions
http://thirdpartyoffers.juno.com/TGL3141/5fbfe09c2b73609b441ast04vuc2
SCOTUS Sides With Religious Groups Over COVID Restrictions
http://thirdpartyoffers.juno.com/TGL3141/5fbfe09c22013609b441ast04vuc3

From n2lxm at juno.com  Thu Nov 26 18:58:32 2020
From: n2lxm at juno.com (n2lxm at juno.com)
Date: Thu, 26 Nov 2020 18:58:32 -0500
Subject: [Milsurplus] TM11-904 Power Units, PE-95-A, -B, -C, -F, -G, and -H
Message-ID: <AABR6CRG3AKJ2DAA@smtpout04.vgs.untd.com>

Good afternoon All,

        While cleaning up and going through Old QST's and other
electronic magazines to take to recycling I came across this TM.  It is
in good shape. So if anyone can use it it's yours for the postage. First
to respond get's it.



                                                    Jeff N2LXM
                                          Amateur Radio Operator
                                                      American
                                                        Patriot
                                     Proud Father of Two US Marines

____________________________________________________________
Sponsored by https://www.newser.com/?utm_source=part&utm_medium=uol&utm_campaign=rss_taglines_more

Cops: Restaurant Owner Went to Extremes to Violate Lockdown
http://thirdpartyoffers.juno.com/TGL3141/5fc13cd976e3a3cd94c26st04vuc1
Trump Says He'll Go If Electoral College Picks Biden
http://thirdpartyoffers.juno.com/TGL3141/5fc13cd99b2923cd94c26st04vuc2
Spy Agency: Kim Is Taking 'Irrational' COVID Measures
http://thirdpartyoffers.juno.com/TGL3141/5fc13cd9bedb53cd94c26st04vuc3

From w2hx at w2hx.com  Fri Nov 27 17:49:12 2020
From: w2hx at w2hx.com (W2HX)
Date: Fri, 27 Nov 2020 22:49:12 +0000
Subject: [Milsurplus] LS-454 for sale
Message-ID: <de038613a0c443d2bf25ad717e31d7cf@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>

Speaking of LS-454's I have one for sale!
https://w2hx.com/forsale?prefix=ForSale/LS-454/

LS-454 very good. I bought this new a few years ago and storage made some scuffs on the bottom but very nice otherwise.
https://w2hx.com/forsame?prefix=ForSale/LS-454/

$30 plus shipping.

73 Eugene W2HX


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201127/d019f5a6/attachment.html>

From k7sz at live.com  Fri Nov 27 19:08:31 2020
From: k7sz at live.com (Rich Arland)
Date: Sat, 28 Nov 2020 00:08:31 +0000
Subject: [Milsurplus] LS-454 for sale
In-Reply-To: <de038613a0c443d2bf25ad717e31d7cf@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>
References: <de038613a0c443d2bf25ad717e31d7cf@EXBE015SV3.NA02.MSEXCHANGEOUTLOOK.COM>
Message-ID: <BN6PR1301MB18734E4EB98EAAE9474B8438F6F70@BN6PR1301MB1873.namprd13.prod.outlook.com>

I'll take it!!!
RICH K7SZ

Sent from my T-Mobile 4G LTE Device
Get Outlook for Android<https://aka.ms/ghei36>

________________________________
From: mrca-bounces at mailman.qth.net <mrca-bounces at mailman.qth.net> on behalf of W2HX <w2hx at w2hx.com>
Sent: Friday, November 27, 2020 5:49:12 PM
To: army-radios at groups.io <army-radios at groups.io>; Military Radio Collectors Association <mrca at mailman.qth.net>; 'MMRCG at groups.io' <MMRCG at groups.io>; West Coast Military Radio Collectors Group <mrcg at mailman.qth.net>; milsurplus at mailman.qth.net <milsurplus at mailman.qth.net>
Subject: [MRCA] LS-454 for sale


Speaking of LS-454?s I have one for sale!

https://w2hx.com/forsale?prefix=ForSale/LS-454/



LS-454 very good. I bought this new a few years ago and storage made some scuffs on the bottom but very nice otherwise.

https://w2hx.com/forsame?prefix=ForSale/LS-454/



$30 plus shipping.



73 Eugene W2HX




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201128/6b681ab6/attachment-0001.html>

From scr287 at att.net  Sat Nov 28 13:52:00 2020
From: scr287 at att.net (Jack Antonio)
Date: Sat, 28 Nov 2020 13:52:00 -0500
Subject: [Milsurplus] Looking for source of mechanical part.
References: <f4a6bb49-4970-f40b-8b77-134b680c5316.ref@att.net>
Message-ID: <f4a6bb49-4970-f40b-8b77-134b680c5316@att.net>

I'm looking for some shaft coupler adapters, that will
let me connect a 1/8" diameter shaft to a 1/4" shaft.

My online searches have only found adapters for larger
shaft sizes than this. Maybe I'm not entering the right
search terms.

Anyone know of a source for these?

Also would be nice to find a 3/8" to 1/4" adapter
as well.

I have a few 1/4" to 1/4" couplers, and could
probably kludge up something, but would like to
do it the right way.

Thanks

Jack Antonio
WA7DIA

From mikebracey at att.net  Sat Nov 28 14:17:31 2020
From: mikebracey at att.net (Mike Bracey)
Date: Sat, 28 Nov 2020 19:17:31 +0000 (UTC)
Subject: [Milsurplus] Looking for source of mechanical part.
In-Reply-To: <f4a6bb49-4970-f40b-8b77-134b680c5316@att.net>
References: <f4a6bb49-4970-f40b-8b77-134b680c5316.ref@att.net>
	<f4a6bb49-4970-f40b-8b77-134b680c5316@att.net>
Message-ID: <837772960.1465789.1606591051917@mail.yahoo.com>

 Wow, that's a tough one Jack. The only thing I could find are repair kits for the Johnson couplers that are 1/4 to 3/16. They are sold on eBay.
Good luck,
Mike Bracey/ KE5YTV


    On Saturday, November 28, 2020, 12:51:35 PM CST, Jack Antonio <scr287 at att.net> wrote:  
 
 I'm looking for some shaft coupler adapters, that will
let me connect a 1/8" diameter shaft to a 1/4" shaft.

My online searches have only found adapters for larger
shaft sizes than this. Maybe I'm not entering the right
search terms.

Anyone know of a source for these?

Also would be nice to find a 3/8" to 1/4" adapter
as well.

I have a few 1/4" to 1/4" couplers, and could
probably kludge up something, but would like to
do it the right way.

Thanks

Jack Antonio
WA7DIA
______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201128/9ef753c5/attachment.html>

From gfsmith at cox.net  Sat Nov 28 15:15:03 2020
From: gfsmith at cox.net (Gordon Smith)
Date: Sat, 28 Nov 2020 12:15:03 -0800
Subject: [Milsurplus] Looking for source of mechanical part.
In-Reply-To: <f4a6bb49-4970-f40b-8b77-134b680c5316@att.net>
References: <f4a6bb49-4970-f40b-8b77-134b680c5316.ref@att.net>
	<f4a6bb49-4970-f40b-8b77-134b680c5316@att.net>
Message-ID: <mailman.556.1606594482.3112.milsurplus@mailman.qth.net>

Hi Jack,
Here is an adapter that should work for you: 
https://smallbear-electronics.mybigcommerce.com/knob-shaft-adapter-1-4-to-1-8/
Same thing from Allied Electronics: 
https://www.alliedelec.com/product/te-connectivity/kr104/70156318/
Here is a different version: 
https://capi-gear.com/catalog/product_info.php?products_id=332

Hope This Helps,

73, Gordon KJ6IKT

At 10:52 AM 11/28/2020, Jack Antonio wrote:
>I'm looking for some shaft coupler adapters, that will
>let me connect a 1/8" diameter shaft to a 1/4" shaft.
>
>My online searches have only found adapters for larger
>shaft sizes than this. Maybe I'm not entering the right
>search terms.
>
>Anyone know of a source for these?
>
>Also would be nice to find a 3/8" to 1/4" adapter
>as well.
>
>I have a few 1/4" to 1/4" couplers, and could
>probably kludge up something, but would like to
>do it the right way.
>
>Thanks
>
>Jack Antonio
>WA7DIA
>______________________________________________________________
>Milsurplus mailing list
>Home: http://mailman.qth.net/mailman/listinfo/milsurplus
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:Milsurplus at mailman.qth.net
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html


From gfsmith at cox.net  Sat Nov 28 15:30:08 2020
From: gfsmith at cox.net (Gordon Smith)
Date: Sat, 28 Nov 2020 12:30:08 -0800
Subject: [Milsurplus] Looking for source of mechanical part.
In-Reply-To: <20201128201441.C99C9149A3E9@mail.qsl.net>
References: <f4a6bb49-4970-f40b-8b77-134b680c5316.ref@att.net>
	<f4a6bb49-4970-f40b-8b77-134b680c5316@att.net>
	<20201128201441.C99C9149A3E9@mail.qsl.net>
Message-ID: <mailman.557.1606595396.3112.milsurplus@mailman.qth.net>

Oh, forgot to mention. If the shafts are self supporting and a 
non-insulated coupling will work, McMaster Carr sells this flexible 
coupling: https://www.mcmaster.com/6208K428/ . Not exactly cheap at 
$42, But it's an option.

73, Gordon KJ6IKT

At 12:15 PM 11/28/2020, Gordon Smith wrote:
>Hi Jack,
>Here is an adapter that should work for you: 
>https://smallbear-electronics.mybigcommerce.com/knob-shaft-adapter-1-4-to-1-8/
>Same thing from Allied Electronics: 
>https://www.alliedelec.com/product/te-connectivity/kr104/70156318/
>Here is a different version: 
>https://capi-gear.com/catalog/product_info.php?products_id=332
>
>Hope This Helps,
>
>73, Gordon KJ6IKT
>
>At 10:52 AM 11/28/2020, Jack Antonio wrote:
>>I'm looking for some shaft coupler adapters, that will
>>let me connect a 1/8" diameter shaft to a 1/4" shaft.
>>
>>My online searches have only found adapters for larger
>>shaft sizes than this. Maybe I'm not entering the right
>>search terms.
>>
>>Anyone know of a source for these?
>>
>>Also would be nice to find a 3/8" to 1/4" adapter
>>as well.
>>
>>I have a few 1/4" to 1/4" couplers, and could
>>probably kludge up something, but would like to
>>do it the right way.
>>
>>Thanks
>>
>>Jack Antonio
>>WA7DIA
>>______________________________________________________________
>>Milsurplus mailing list
>>Home: http://mailman.qth.net/mailman/listinfo/milsurplus
>>Help: http://mailman.qth.net/mmfaq.htm
>>Post: mailto:Milsurplus at mailman.qth.net
>>
>>This list hosted by: http://www.qsl.net
>>Please help support this email list: http://www.qsl.net/donate.html
>
>______________________________________________________________
>Milsurplus mailing list
>Home: http://mailman.qth.net/mailman/listinfo/milsurplus
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:Milsurplus at mailman.qth.net
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html


From Kargo_cult at msn.com  Sat Nov 28 19:12:15 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sun, 29 Nov 2020 00:12:15 +0000
Subject: [Milsurplus] FW: Earphone cushions question
In-Reply-To: <MWHPR22MB02692B91D7E28BC552FA5977E4F70@MWHPR22MB0269.namprd22.prod.outlook.com>
References: <MWHPR22MB02692B91D7E28BC552FA5977E4F70@MWHPR22MB0269.namprd22.prod.outlook.com>
Message-ID: <MWHPR22MB026912C60FFF85AE8A12FB60E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>

Today I was getting a couple Heil headsets ready to put on Ebay. On the HC-5, I 
replaced headphone 3 items in this order: a thin foam disc that goes right up 
against the earphone element face; the rubber earphone "earpads" ( = cushions,
which also hold this foam disc down ( and are a challenge to stretch around the 
perimeter of the earpiece ); and the "earpad covers", which are a kind of elastic
rimmed sock that pulls over the whole earphone element, open at back for wire
lead escape. 
The experience popped an idea into my head: are any of these Heil replacement
parts adaptable to military headsets, say like the USAAF headphones or the TBY
headphone, for example? 
What think?
It comes to me now that the Heil elements have a thin rim, outer edge which
is quite a bit different from antique headphones. After my struggle putting 
those on the HC-5, I am not going to take them off again now to explore their 
use with older earphones. 
I sent the below note to the 'DX Store'  dxstore.com
I would probably be silly enough to buy a selection and try them. If none of the 
cushions happen to work out, even the "sock" covers would be an improvement
over naked earphone, and also limit the soiling of the headphone. 
( Sorry, 'soiling' is an antiquated word from an OT. )
-Hue Miller

Letter sent to DX Store:

"Say, this will be kind of an oddball question.
I just put on new ear cushions and so on, on a Heil HC-5 set.
The cushions got me to thinking: I have a number of WW2 military earphone sets whose
cushions are no longer available, and the old ones, even if NOS, are most often stiff and 
cracked. So I am wondering if maybe some of your Heil replacements would be suitable 
for this use. I suppose the only way to really check this is to buy an assortment and just
try them all out. The HC-5 types I used today definitely won't do, as they have an oblong 
shape, while the military earpieces are all round an d with a diameter of 2-1/4 to 2-1/2 inches. 
What think? Any thoughts on the adaptability?"

From Kargo_cult at msn.com  Sat Nov 28 19:24:01 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sun, 29 Nov 2020 00:24:01 +0000
Subject: [Milsurplus] Earphone cushions question
In-Reply-To: <MWHPR22MB026912C60FFF85AE8A12FB60E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>
References: <MWHPR22MB02692B91D7E28BC552FA5977E4F70@MWHPR22MB0269.namprd22.prod.outlook.com>
	<MWHPR22MB026912C60FFF85AE8A12FB60E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>
Message-ID: <MWHPR22MB0269CA872D246B4926FB3B6CE4F60@MWHPR22MB0269.namprd22.prod.outlook.com>

As an addendum to my last, I recalled seeing new reproduction Panzer headphone
cushions. I found the place that had them, now sold out: 
https://www.warsendshop.com/products/panzer-headset-replacement-earpads
and mention this here possibly for those curious. However, it doesn't appear these
would nicely fit our headphones anyway, and they really are way too large for U.S.
type. I suppose the large size was to better suppress external noise.
-Hue Miller 

From Kargo_cult at msn.com  Sat Nov 28 22:19:30 2020
From: Kargo_cult at msn.com (Hubert Miller)
Date: Sun, 29 Nov 2020 03:19:30 +0000
Subject: [Milsurplus] One more for the GRC-9
Message-ID: <MWHPR22MB02696E9F6063582E65DE0777E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>

I was putting away things tonight including some LEDs when it occurred to me, I just
have to try this. The GRC-9 lamp is bayonet socket. You can buy an LED bulb in similar
size but screw base. If you take needle pliers and bend the top tab of the bayonet holder,
that tab just above the two nibs on the bayonet bulb, bend this tab ever so slightly in,
the LED bulb can force fit into the socket, even without using its threads. This lamp
delivers a warm white light, much better than the original feeble #49 bulb, and draws
80 mA.  This photo was done in darkness. Recommended for rear - area usage only.
-Hue Miller

[A picture containing car, sitting, meter, close  Description automatically generated]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201129/fd54769e/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 89785 bytes
Desc: image001.jpg
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201129/fd54769e/attachment-0001.jpg>

From Captain.Kelly at outlook.com  Sun Nov 29 15:19:22 2020
From: Captain.Kelly at outlook.com (Sean Kelly)
Date: Sun, 29 Nov 2020 20:19:22 +0000
Subject: [Milsurplus] One more for the GRC-9
In-Reply-To: <MWHPR22MB02696E9F6063582E65DE0777E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>
References: <MWHPR22MB02696E9F6063582E65DE0777E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>
Message-ID: <BYAPR19MB242275DC47D23845D9D1FFF5F5F60@BYAPR19MB2422.namprd19.prod.outlook.com>

________________________________

Subject: [Army-Radios] One more for the GRC-9


I was putting away things tonight including some LEDs when it occurred to me, I just

have to try this. The GRC-9 lamp is bayonet socket. You can buy an LED bulb in similar

size but screw base. If you take needle pliers and bend the top tab of the bayonet holder,

that tab just above the two nibs on the bayonet bulb, bend this tab ever so slightly in,

the LED bulb can force fit into the socket, even without using its threads.


11/19/2019:


If you have a bayonet socket in open air, you can bend one of the top "lips" in slightly.



Seems I have a selective memory.


Sean
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201129/c39fc443/attachment.html>

From mark.k3msb at gmail.com  Mon Nov 30 19:45:18 2020
From: mark.k3msb at gmail.com (Mark K3MSB)
Date: Mon, 30 Nov 2020 19:45:18 -0500
Subject: [Milsurplus] Cinch Jones Connector
Message-ID: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>

Hello

I'm looking to make an extension cable that uses the Cinch Jones connector
shown here:

www.k3msb.com/temp/Cinch_001.jpg
www.k3msb.com/temp/Cinch_002.jpg
www.k3msb.com/temp/Cinch_003.jpg
www.k3msb.com/temp/Cinch_004.jpg

>From searching the web,  I think the connectors are

Cinch P5412CCT Jones 12 Pin Plug 38541-5412 Connector
Cinch S5412CCT Jones 12 Pin Socket 38541-8412 Connector Cable Clamp Top

I can't find any web site that shows explicit dimensions though.

Any help appreciated.

73 Mark K3MSB
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/91a86b1a/attachment.html>

From n4fs at eozinc.com  Mon Nov 30 20:04:14 2020
From: n4fs at eozinc.com (Mike Feher)
Date: Mon, 30 Nov 2020 20:04:14 -0500
Subject: [Milsurplus] [ARC5] Cinch Jones Connector
In-Reply-To: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
References: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
Message-ID: <1e3c01d6c77d$e33418d0$a99c4a70$@eozinc.com>

I thought that style was called Motorola connectors. 73 ? Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

From: arc5-bounces at mailman.qth.net <arc5-bounces at mailman.qth.net> On Behalf Of Mark K3MSB
Sent: Monday, November 30, 2020 7:45 PM
To: ARC5 <arc5 at mailman.qth.net>; List Milsurplus <milsurplus at mailman.qth.net>
Subject: [ARC5] Cinch Jones Connector

 

Hello

 

I'm looking to make an extension cable that uses the Cinch Jones connector shown here:

 

www.k3msb.com/temp/Cinch_001.jpg <http://www.k3msb.com/temp/Cinch_001.jpg> 

www.k3msb.com/temp/Cinch_002.jpg <http://www.k3msb.com/temp/Cinch_002.jpg>  

www.k3msb.com/temp/Cinch_003.jpg <http://www.k3msb.com/temp/Cinch_003.jpg>  

www.k3msb.com/temp/Cinch_004.jpg <http://www.k3msb.com/temp/Cinch_004.jpg>  

 

>From searching the web,  I think the connectors are 

 

Cinch P5412CCT Jones 12 Pin Plug 38541-5412 Connector 
Cinch S5412CCT Jones 12 Pin Socket 38541-8412 Connector Cable Clamp Top

 

I can't find any web site that shows explicit dimensions though.

 

Any help appreciated.

 

73 Mark K3MSB

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/6cad273b/attachment-0001.html>

From n4fs at eozinc.com  Mon Nov 30 20:04:58 2020
From: n4fs at eozinc.com (Mike Feher)
Date: Mon, 30 Nov 2020 20:04:58 -0500
Subject: [Milsurplus] Cinch Jones Connector
In-Reply-To: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
References: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
Message-ID: <1e4101d6c77d$fda7f290$f8f7d7b0$@eozinc.com>

I thought that style was called Motorola connectors. 73 ? Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Mark K3MSB
Sent: Monday, November 30, 2020 7:45 PM
To: ARC5 <arc5 at mailman.qth.net>; List Milsurplus <milsurplus at mailman.qth.net>
Subject: [Milsurplus] Cinch Jones Connector

 

Hello

 

I'm looking to make an extension cable that uses the Cinch Jones connector shown here:

 

www.k3msb.com/temp/Cinch_001.jpg <http://www.k3msb.com/temp/Cinch_001.jpg> 

www.k3msb.com/temp/Cinch_002.jpg <http://www.k3msb.com/temp/Cinch_002.jpg>  

www.k3msb.com/temp/Cinch_003.jpg <http://www.k3msb.com/temp/Cinch_003.jpg>  

www.k3msb.com/temp/Cinch_004.jpg <http://www.k3msb.com/temp/Cinch_004.jpg>  

 

>From searching the web,  I think the connectors are 

 

Cinch P5412CCT Jones 12 Pin Plug 38541-5412 Connector 
Cinch S5412CCT Jones 12 Pin Socket 38541-8412 Connector Cable Clamp Top

 

I can't find any web site that shows explicit dimensions though.

 

Any help appreciated.

 

73 Mark K3MSB

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/fec208d2/attachment.html>

From w2hx at w2hx.com  Mon Nov 30 20:32:06 2020
From: w2hx at w2hx.com (W2HX)
Date: Tue, 1 Dec 2020 01:32:06 +0000
Subject: [Milsurplus] Cinch Jones Connector
In-Reply-To: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
References: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
Message-ID: <f3ba621d00334daeb4225fbd863700db@EXBE014SV3.NA02.MSEXCHANGEOUTLOOK.COM>

https://www.ebay.com/itm/131944614840


From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Mark K3MSB
Sent: Monday, November 30, 2020 7:45 PM
To: ARC5 <arc5 at mailman.qth.net>; List Milsurplus <milsurplus at mailman.qth.net>
Subject: [Milsurplus] Cinch Jones Connector

Hello

I'm looking to make an extension cable that uses the Cinch Jones connector shown here:

www.k3msb.com/temp/Cinch_001.jpg<http://www.k3msb.com/temp/Cinch_001.jpg>
www.k3msb.com/temp/Cinch_002.jpg<http://www.k3msb.com/temp/Cinch_002.jpg>
www.k3msb.com/temp/Cinch_003.jpg<http://www.k3msb.com/temp/Cinch_003.jpg>
www.k3msb.com/temp/Cinch_004.jpg<http://www.k3msb.com/temp/Cinch_004.jpg>

From searching the web,  I think the connectors are

Cinch P5412CCT Jones 12 Pin Plug 38541-5412 Connector
Cinch S5412CCT Jones 12 Pin Socket 38541-8412 Connector Cable Clamp Top

I can't find any web site that shows explicit dimensions though.

Any help appreciated.

73 Mark K3MSB
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201201/1c4b4666/attachment.html>

From n4fs at eozinc.com  Mon Nov 30 21:54:59 2020
From: n4fs at eozinc.com (Mike Feher)
Date: Mon, 30 Nov 2020 21:54:59 -0500
Subject: [Milsurplus] [ARC5] Cinch Jones Connector
In-Reply-To: <0c7601d6c78b$9d449f30$d7cddd90$@cox.net>
References: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>	<1e3c01d6c77d$e33418d0$a99c4a70$@eozinc.com>
	<0c7601d6c78b$9d449f30$d7cddd90$@cox.net>
Message-ID: <1e9f01d6c78d$5bec0940$13c41bc0$@eozinc.com>

Yep, you are right. I was thinking Jones but said Motorola. 73 ? Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

From: arc5-bounces at mailman.qth.net <arc5-bounces at mailman.qth.net> On Behalf Of Scott Johnson
Sent: Monday, November 30, 2020 9:42 PM
To: 'Mike Feher' <n4fs at eozinc.com>; 'Mark K3MSB' <mark.k3msb at gmail.com>; 'ARC5' <arc5 at mailman.qth.net>; 'List Milsurplus' <milsurplus at mailman.qth.net>
Subject: Re: [ARC5] Cinch Jones Connector

 

Jones plugs.

Motorola plug is the automotive antenna connector.

 

Scott V. Johnson W7SVJ

5111 E. Sharon Dr.

Scottsdale, AZ 85254-3636

H (602) 953-5779

C (480) 550-2358

 <mailto:scottjohnson1 at cox.net> scottjohnson1 at cox.net

 <mailto:scott.johnson at ieee.org> scott.johnson at ieee.org

 

From: arc5-bounces at mailman.qth.net <mailto:arc5-bounces at mailman.qth.net>  <arc5-bounces at mailman.qth.net <mailto:arc5-bounces at mailman.qth.net> > On Behalf Of Mike Feher
Sent: Monday, November 30, 2020 6:04 PM
To: 'Mark K3MSB' <mark.k3msb at gmail.com <mailto:mark.k3msb at gmail.com> >; 'ARC5' <arc5 at mailman.qth.net <mailto:arc5 at mailman.qth.net> >; 'List Milsurplus' <milsurplus at mailman.qth.net <mailto:milsurplus at mailman.qth.net> >
Subject: Re: [ARC5] Cinch Jones Connector

 

I thought that style was called Motorola connectors. 73 ? Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/017411f1/attachment-0001.html>

From jphutch60bj at gmail.com  Mon Nov 30 22:44:54 2020
From: jphutch60bj at gmail.com (jphutch60bj)
Date: Mon, 30 Nov 2020 21:44:54 -0600
Subject: [Milsurplus] One more for the GRC-9
In-Reply-To: <MWHPR22MB02696E9F6063582E65DE0777E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>
References: <MWHPR22MB02696E9F6063582E65DE0777E4F60@MWHPR22MB0269.namprd22.prod.outlook.com>
Message-ID: <620889e4-b568-9e52-8a1c-ac9dd3f5a790@gmail.com>

try this no bending needed:

https://www.grainger.com/product/39P458?gclid=EAIaIQobChMI3Je8tu6r7QIVrYFaBR3X4AWvEAQYBCABEgIctfD_BwE&cm_mmc=PPC:+Google+PLA&ef_id=EAIaIQobChMI3Je8tu6r7QIVrYFaBR3X4AWvEAQYBCABEgIctfD_BwE:G:s&s_kwcid=AL!2966!3!281698275483!!!g!469738748142!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231

  * Item Miniature LED Lamp
  * Overall Bulb Shape T
  * Bulb Shape T3-1/4
  * Overall Bulb Base Type Miniature Bayonet
  * Bulb Base Type Miniature Bayonet (BA9s)
  * Light Technology LED
  * Lumens 10
  * Wattage Equivalency 0.3W INC
  * Watts 0.3W? <--
  * Voltage 6V AC <--
  * Trade Number L1006MB-W
  * Bulb Primary Application General Purpose
  * Bulb Type Miniature
  * Light Appearance 5000K and Above, Daylight
  * Indoor/Outdoor Usage Indoor Only
  * Dimmable No
  * Light Color White
  * Bulb Housing Glass
  * Bulb Dia. 7/16 in
  * Overall Length 1 13/64 in
  * Rated Life 20,000 hr
  * Amps 12mA
  * Bulb Power Source Direct Wired
  * For Enclosed Fixtures No
  * Green Environmental Attribute Product Contributes To Reducing Energy
    Consumption



On 11/28/2020 9:19 PM, Hubert Miller wrote:
>
> I was putting away things tonight including some LEDs when it occurred 
> to me, I just
>
> have to try this. The GRC-9 lamp is bayonet socket. You can buy an LED 
> bulb in similar
>
> size but screw base. If you take needle pliers and bend the top tab of 
> the bayonet holder,
>
> that tab just above the two nibs on the bayonet bulb, bend this tab 
> ever so slightly in,
>
> the LED bulb can force fit into the socket, even without using its 
> threads. This lamp
>
> delivers a warm white light, much better than the original feeble #49 
> bulb, and draws
>
> 80 mA.? This photo was done in darkness. Recommended for rear ? area 
> usage only.
>
> -Hue Miller
>
> A picture containing car, sitting, meter, close Description 
> automatically generated
>
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/d5f04dfa/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 89785 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/d5f04dfa/attachment-0001.jpg>

From mark.k3msb at gmail.com  Mon Nov 30 22:55:14 2020
From: mark.k3msb at gmail.com (Mark K3MSB)
Date: Mon, 30 Nov 2020 22:55:14 -0500
Subject: [Milsurplus] [ARC5] Cinch Jones Connector
In-Reply-To: <SA0PR07MB7595749E312F9D610DB4A3CDF1F40@SA0PR07MB7595.namprd07.prod.outlook.com>
References: <CABdVoaCghhgnqjsuOiVi-o6SZCQbpuL3WZSw3PTJPvqbm0_oJA@mail.gmail.com>
	<SA0PR07MB7595749E312F9D610DB4A3CDF1F40@SA0PR07MB7595.namprd07.prod.outlook.com>
Message-ID: <CABdVoaDOT_QGEaDRrzKT_GTUaN-hehzF+dp-0B-wgaFks5VWDg@mail.gmail.com>

I also found them on ebay and copied the names from the auctions into my
initial post:

Cinch P5412CCT Jones 12 Pin Plug 38541-5412 Connector
Cinch S5412CCT Jones 12 Pin Socket 38541-8412 Connector Cable Clamp Top

What I'm looking for is verification that those will fit the connector in
my photos.

Mark K3MSB



On Mon, Nov 30, 2020 at 10:31 PM D C _Mac_ Macdonald <k2gkk at hotmail.com>
wrote:

> I found both with Google on eBay in a few minutes.
>
> Female is $20 and male is $30.
>
> 73 - Mac, K2GKK/5
> Since 30 Nov 1953
> Oklahoma City, OK
> USAF (Retired) 61-81
> FAA (Retired) 94-10
> ------------------------------
> *From:* arc5-bounces at mailman.qth.net <arc5-bounces at mailman.qth.net> on
> behalf of Mark K3MSB <mark.k3msb at gmail.com>
> *Sent:* Monday, November 30, 2020 18:45
> *To:* ARC5 <arc5 at mailman.qth.net>; List Milsurplus <
> milsurplus at mailman.qth.net>
> *Subject:* [ARC5] Cinch Jones Connector
>
> Hello
>
> I'm looking to make an extension cable that uses the Cinch Jones connector
> shown here:
>
> www.k3msb.com/temp/Cinch_001.jpg
> <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.k3msb.com%2Ftemp%2FCinch_001.jpg&data=04%7C01%7C%7C4cebaa9cb51845962f3208d89592910d%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637423804010873085%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=buvNXhbFuASwszMOEhyhCT906lWwyzf4dRw2dPCcsgo%3D&reserved=0>
> www.k3msb.com/temp/Cinch_002.jpg
> <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.k3msb.com%2Ftemp%2FCinch_002.jpg&data=04%7C01%7C%7C4cebaa9cb51845962f3208d89592910d%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637423804010883082%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=6ZvCPB57tS7JcFwRJ6qgiYQhtG%2BjBJOcxoOiWm5EnOY%3D&reserved=0>
> www.k3msb.com/temp/Cinch_003.jpg
> <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.k3msb.com%2Ftemp%2FCinch_003.jpg&data=04%7C01%7C%7C4cebaa9cb51845962f3208d89592910d%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637423804010893084%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=1t8oYqiAIxE42NMRoq8dBHubfiZTJkaEmHxBWH1h4DI%3D&reserved=0>
> www.k3msb.com/temp/Cinch_004.jpg
> <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.k3msb.com%2Ftemp%2FCinch_004.jpg&data=04%7C01%7C%7C4cebaa9cb51845962f3208d89592910d%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637423804010903080%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=MdMhL66R%2FjFmaNXmaYPlBHPiv2prgcCxk8lfKsPEU2Q%3D&reserved=0>
>
> From searching the web,  I think the connectors are
>
> Cinch P5412CCT Jones 12 Pin Plug 38541-5412 Connector
> Cinch S5412CCT Jones 12 Pin Socket 38541-8412 Connector Cable Clamp Top
>
> I can't find any web site that shows explicit dimensions though.
>
> Any help appreciated.
>
> 73 Mark K3MSB
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/d39b9c4b/attachment.html>

From arc5 at ix.netcom.com  Mon Nov 30 23:06:55 2020
From: arc5 at ix.netcom.com (David Stinson)
Date: Mon, 30 Nov 2020 22:06:55 -0600
Subject: [Milsurplus] Seeking Aussie AT5 Radio Covers
Message-ID: <d99f7ce2-47e4-9445-add9-7d9c8ebb9cbe@ix.netcom.com>

Cleaning and dusting-off some gear when I
happened-upon one of my favourite non-US
WWII sets, the Australian AT5-AR8 set.
The AT5 transmitter is still missing all of its
covers.? Using Perspex as a sub.
I have things to trade and/or cash.
Anyone have any leads on AT5 covers?
TNX OM ES 73 De Dave AB5S




-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/408f3711/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: haccnbjlnbiccoja.jpg
Type: image/jpeg
Size: 143335 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201130/408f3711/attachment-0001.jpg>

From kargo_cult at msn.com  Mon Nov 30 23:29:23 2020
From: kargo_cult at msn.com (Owner)
Date: Tue, 01 Dec 2020 04:29:23 +0000
Subject: [Milsurplus] Seeking Aussie AT5 Radio Covers
In-Reply-To: <d99f7ce2-47e4-9445-add9-7d9c8ebb9cbe@ix.netcom.com>
References: <d99f7ce2-47e4-9445-add9-7d9c8ebb9cbe@ix.netcom.com>
Message-ID: <MWHPR22MB0269B21ED2AE632C67FB759FE4F40@MWHPR22MB0269.namprd22.prod.outlook.com>

>A particular reason you used plastics instead of sheet aluminum for the 
>cover?
>Easier to work with? I have something of the same challenge, but hadn't 
>thought at all of using plastic.
>Real nice looking gear, Dave.
>In fact, i am feeling hard pressed to think of any pair i have that's 
>as neat-o.
>-Hue Miller
>


From kargo_cult at msn.com  Mon Nov 30 23:41:45 2020
From: kargo_cult at msn.com (Owner)
Date: Tue, 01 Dec 2020 04:41:45 +0000
Subject: [Milsurplus] One more for the GRC-9
In-Reply-To: <620889e4-b568-9e52-8a1c-ac9dd3f5a790@gmail.com>
References: <MWHPR22MB02696E9F6063582E65DE0777E4F60@mwhpr22mb0269.namprd22.prod.outlook.com>
	<620889e4-b568-9e52-8a1c-ac9dd3f5a790@gmail.com>
Message-ID: <MWHPR22MB02695E158B7A9EF64D55CBBAE4F40@MWHPR22MB0269.namprd22.prod.outlook.com>

6 volts is a multiple of the 1.5 volts supply in the GRC-9.  I suspect, 
tho not positive, it will not work
down that far below spec. The 222 replacement LED bulb, rated for 1.5 
volt, will operate down to
0.5 volt. I might order the 6 volt bulb just to see. Or i'll ask around.

My next little experiment will be to solder right to the LED bulb base. 
I know i could get away with
this with incandescent bulb, and maybe using a 35w pen and a quick hand 
i can keep from destroying
the innards.
-Hue
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20201201/ab2b419a/attachment.html>

