[GreenKeys] Model 28 Typing Unit activated immediately at power-up. What's stuck?

[Tim Griffin]

Hi all;

I have just joined Green Keys because of my acquisition of a Teletype Model
28 KSR, that appears complete and semi-operational, and am seeking a little
diagnostic expertise before I start hunting too much. I have downloaded
many manuals and service bulletins for the unit, and am definitely
intimated by the myriad adjustment procedures that I'm not keen to touch
anything until I know where I'm headed.

I've posted a short video that illustrates what the machine is doing as
soon as it's powered up.

https://www.dropbox.com/s/gda9n2j3gxh0tl5/Teletype.MOV?dl=0

It begins "printing", and while the ribbon advances, there is no print head
advancement, and the Keyboard Lock key jumps up and down at each cycle. The
teletype is not connected to any signal source, so this behaviour suggests
something stuck, worn out, worn down... I'm not sure what.

Can anyone give me a general sense of things to consider at this initial
stage?

As a little background, I'm a collector of telephony equipment here in
Canada (Step-by-Step, switchboards, intercoms, telephones etc.) as well as
some vintage computers, and IBM Selectric typewriters. All of these things
are challenging to master, but I'm seeing this Model 28 as perhaps the
biggest challenge yet! The unit I've acquired was once in service in the
Canadian National (Railway) office in Chicoutimi, Québec, in use up until
about 1977. (It's equipped with a 7.5" sprocket-feed platen (rather than
8.5"), so my guess is that it was used for printing rail tickets, forms
etc. but that means I'm also on the hunt for either 7.5" sprocket paper
(none found yet anywhere), or an 8.5" sprocket-feed platen that would allow
me to use regular bi-fold computer paper.)

But, before it prints anything for real, any pointers on its current
behaviour would be most welcome as a start!

Tim Griffin
Ottawa, Canada
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