[GreenKeys] 28 ASR running open

[Sarah Autumn]

Haha, right on :) I'll let you know if anything else blows up. Thanks again!

On Fri, Jul 17, 2015 at 11:51 AM Jack <wa2hwj at att.net> wrote:

> Sarah,
>
>
>
> Remember: when it works, don’t fix it!
>
>
>
> If I can be of any more help, let me know. Model 28’s
>
> are my life-long friends!
>
>
>
> Jack
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>
>
> *From:* Sarah Autumn [mailto:neverether at gmail.com]
> *Sent:* Friday, July 17, 2015 10:56 AM
> *To:* Jack; greenkeys at mailman.qth.net
>
>
> *Subject:* Re: [GreenKeys] 28 ASR running open
>
>
>
> A ha! I got it. Whoever converted the machine had jumper wires from the
> keyboard terminals on the cabinet terminal strip over to two other
> terminals near near the TD (i think 129 and 130?). I grew suspicious of
> those, and removed them. In doing so, I also found that the keyboard was
> connected to #3 terminal, and it should have been connected to 9 or 10.
> (Can't remember which. I'm not in front of it right now). So removing the
> weird extra wires, and moving the keyboard to the correct spot fixed it.
>
>
>
> I'm not sure what those jumper wires were doing in the first place, and
> I'm not sure why it worked before this. Maybe when I shorted out the wires
> earlier I moved something around that messed with the modified wiring.
>
>
>
> Thanks for the help! Looks like talking through the problem led us to the
> right spot :)
>
>
>
> On Fri, Jul 17, 2015 at 7:08 AM, Jack <wa2hwj at att.net> wrote:
>
> Sarah,
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>
>
> It sounds like something is shorted. Try to manually
>
> operate the keyboard contacts (in the “do no oil” box). Unplug
>
> the keyboard connector in the back so there’s no voltage on the contacts
>
> and use an ohm meter to see if the contacts open and close when
>
> you hit a key and manually turn the motor. If that works, then you
>
> have a short somewhere else in the wiring.
>
>
>
> You can check the keyboard-to-connector wiring the same way.
>
> Just connect the ohm meter to the pins on the connector. I believe it’s
>
> pin 0 and 2.
>
>
>
> Does the BREAK key make the machine run open? It’s not always
>
> wired in, but it’s worth a check.
>
>
>
> Jack
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>
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>
> *From:* Sarah Autumn [mailto:neverether at gmail.com]
> *Sent:* Friday, July 17, 2015 1:35 AM
> *To:* Jack
> *Subject:* Re: [GreenKeys] 28 ASR running open
>
>
>
> Also, I'm not sure if this is relevant information, but if I hook up my
> oscilloscope to either of the keyboard posts on the cabinet terminal block
> (3 and 10), I don't get any intelligence--that is to say that I just get a
> consistent voltage, but no voltage dips or spikes if I type. It seems as
> though typing doesnt send any signal at all from the signal generator.
>
>
>
> Again, I'm still learning so I might be wrong in my assumption of how this
> is supposed to work. Thanks again!
>
> -Sarah
>
>
>
> On Thu, Jul 16, 2015 at 11:28 PM, Sarah Autumn <neverether at gmail.com>
> wrote:
>
>
>
> Hi Jack,
>
>
>
> Thank you for your reply :)
>
>
>
> There appears to be 2 springs to the right of the signal generator box.
> One is longer, and closer to the operators sitting position, and one is
> shorter, about 1/2' further back. Both are present, and attached.
>
>
>
> The connector at the rear of the keyboard from the ESU is firmly attached,
> and all contacts look good.
>
>
>
> The feature on the stunt box that blocked the keyboard worked consistently
> up until now. When I hit the "Blank" key twice, the keyboard would lock,
> but it would not run open making a racket like it is now.
>
>
>
> The microswitch you mentioned and all of the levers beneath where the
> typing unit sits appear to be moving freely.
>
>
>
> I removed the stunt box in order to add another switch assembly to it. I
> set up FIGS 'J' to trip a contact. The switch is installed, but not wired
> in to anything. There is an existing switch that was already there that
> rings the bell on FIGS 'S'. I also unblocked the two or three function bars
> farthest to the left if looking at it from the operators position.
>
>
>
> On Thu, Jul 16, 2015 at 6:44 PM, Jack <wa2hwj at att.net> wrote:
>
> The keyboard should be a short circuit when idle (it’s a switch).
>
> There should be a small spring just to the right of the “signal generator
>
> box” on the keyboard that holds two latches together. Make
>
> sure you didn’t knock that loose (it happens). That could
>
> cause the keyboard contacts go open.
>
>
>
> Also make sure the connector on the rear of the keyboard.
>
>
>
> Make sure the typing unit did not jam the “BREAK”
>
> microswitch that’s in the middle of the keyboard base.
>
>
>
> There’s a set of function bars on the stunt box that will activate the
>
> SEND/RECEIVE keys when a series of “BLANKS” is received
>
> or the line goes open, causing the keyboard to lock and/or
>
> be blocked.
>
>
>
> What did you do to the stuntbox?
>
>
>
> Jack K0TTY
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>
> *From:* GreenKeys [mailto:greenkeys-bounces at mailman.qth.net] *On Behalf
> Of *Sarah Autumn
> *Sent:* Thursday, July 16, 2015 8:05 PM
> *To:* greenkeys at mailman.qth.net
> *Subject:* [GreenKeys] 28 ASR running open
>
>
>
> Hey all,
>
>
>
> My 28 is running open, and I feel like I'm missing something obvious. I'll
> try to provide a list of what I have, and what I've done...
>
>
>
> -Pretty much stock 28 ASR, though it has been modified for the deaf, and I
> provide loop current with an acoustic coupler modem.
>
> -Previous to last week, it ran without any problems.
>
> -Runs fine as long as keyboard is not plugged in to the loop. I also have
> an original 100A Teletype Test Distributor, that I've plugged in through
> keyboard plug of the modem, and it works great. The typing unit behaves
> properly.
>
>
>
> So I don't think it's the modem. I've checked the signal coming out of the
> contact box / signal generator, but I'm not sure what I should be looking
> for. I get constant voltage on one terminal, and constantly no voltage on
> the other. Hitting keys seems to have no effect, though the little wiggly
> bits inside wiggle nicely.
>
>
>
> Symptoms started when I had the typing unit out to work on the stunt box.
> Finally got that how I want it, and when I put the typing unit back in for
> the last time, a wire on the connector must have gotten stuck, and it
> shorted. I fixed the wires, and the TU appears to be fine.
>
>
>
> What am I looking for coming out of the signal generator? Am I barking up
> the wrong tree?
>
>
>
> Thanks :)
>
> Sarah
>
>
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>
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