Altair Replica and Stuff

[n0jcf]

Originally Posted by phe

Hi Guys. I did not get my teletype working, but now you have inspired me. Sorry, Tom, but I cannot help you yet but perhaps I can if I get mine working.

My problem is that I do not know if my teletype is current loop or RS-232. Do either of you know how I can figure this out? Are there pin voltage settings I could measure? I've always held off because I did not want to take any chances of frying my 2SIO port or my teletype. Would a wrong (mismatched) connection cause harm?

If it is a genuine Teletype model 33, then it is 20mA. Teletype did not build any model
33 with RS232. They were all current loop. It would only be RS232 if there was a
current loop to RS232 converter installed inside or outboard somewhere.

Teletype model 43 is possibly RS232... but this is a much more modern "teletype" and is mostly electronic (with dot matrix printhead) rather than the nearly all mechanical model 33.

Chris