[GreenKeys] Teletype ASR model 33 restoration

[Benoit Aveline]

Hi,

Recently I recovered 2 model 33 teletypes from 1976. Both are the same, 
and both haven't been plugged since 30+ years. The old man who gave them 
to me got them at his factory when they decommissioned those. His plan 
was to plug them to each other in 2 different rooms for his kids to play 
with them. He never did.
So, having both, I started to restore one, keeping the other one for 
spare parts.
Here is a picture of one before I start cleaning:

https://imgbb.com/D7k8By0

They have been modified by a retailer for France use (220V 50Hz).
So I cleaned one, de-greased and re-greased most of it, changed a broken 
ball bearing shaft (taken from the other one), checked the relays were 
not stuck (with a 12V lab psu) and replaced the rubber hammer on the 
print head with a rubber tube (the 40yo rubber hammer was turning into 
some sticky nasty gum).
I'm close to make it work locally. I still have to fine tune some 
settings and make the Carriage Return work, but the four blocks work 
(just with a very low reliability on decoding characters).
My intent was to use Mike's "current loop to rs232" adapter ( 
https://deramp.com/tty_adapter.html ), but the P2 connector looks a 
little bit different. Its pin 3 isn't wired (which is where the adapter 
gets power from).

https://ibb.co/YTMGV4n

https://ibb.co/TRKfJ3z

https://ibb.co/fF83Yxd

So, the UCC neither a UCC-6 or a telex. I don't even know if P2 
connector is wired as the one on UCC-6.

Has anyone seen that kind of UCC ? Does anyone has some information or 
documentation about it ?

And does anyone know about decoding reliability or carriage return issue 
? I already ordered new capacitors to replace all of them, as it can't hurt.

Thank you

Ben