[GreenKeys] 28 ASR running open

[Sarah Autumn]

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,
>
>
>
> 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
>
>
>
>
>
>
>
>
>
> *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
>
>
>
>
>
>
>
>
>
> *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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