[GreenKeys] Seeking Teletype Part 1882241

[Eric Moore]

I really have no idea the expected behavior, this is the first time it has
run without almost immediately seizing since I have owned it. The seizing
issue, a gentleman who was able to come over found and resolved as a
mis-adjusted component to the left standing in front of the teletype above
the main shaft.

I was going to follow the maintenance procedures on the wiki before further
troubleshooting, thank you for the diagnosis on what you see in the video.
There appears to be a ground fault with the teletype that is preventing the
system bus from being used when the teletype itself is energized. It is in
fact setting a bit in one of the computers registers. The teletype itself
can be bypassed luckily with an adapter, which is what I have been doing up
until now.

After basic maintenance I was hoping to get to expected behavior when in
local, then was going to use an RS232 adapter to test online mode with the
teletype off its pedestal, and use that opportunity to try and find the
ground fault.

Is maintenance easier to perform with the teletype removed from its base?

Thank you,

-Eric




On Sat, Jun 5, 2021 at 3:13 PM Jim Cooper <jim.w2jc at gmail.com> wrote:

> On 5 Jun 2021 at 15:03, Eric Moore wrote:
>
> >  Pictures of the system were
> > requested, so please find this video
> > URL below.
> >
> > https://youtu.be/KCx2kGycYQ0
>
> you have no paper in the platen ...
> what is it printing when it is making the noise?
>
> is it just 'running open' or is it actually printing
> something?   the typer is moving to the right,
> so it looks like it's trying to print something.
>
> in the on-line mode it seems to be quite,
> indicating the loop is closed and no signals are
> coming in ...
>
> in the local mode it seems erratic, or an open
> loop -- or a loop with something that has a
> 'loose contact' and is erratically keying the local
> loop ...
>
> that's my impression.
>
> w2jc
>
>
>
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