Altair Replica and Stuff

[phe]

Originally Posted by TomL_12953

You can check it without connecting it to your Altair. Plug in the Teletype to the AC outlet. Turn the Line/Off/Local knob to Line (all the way counterclockwise if you don't have the front aluminum escuheon). If the TTY starts chattering without printing anything, it's 20mA Current Loop. If it stays silent, it's RS-232.

Thanks, Tom. OK, I have RS-232. Thanks for helping me figure that out. But it means that I can't try to replicate your setup on my equipment or offer any helpful suggestions. I'll just fade into the woodwork now..... Sorry for interrupting your thread.

Paul

[TomL_12953]

Originally Posted by phe

Thanks, Tom. OK, I have RS-232. Thanks for helping me figure that out. But it means that I can't try to replicate your setup on my equipment or offer any helpful suggestions. I'll just fade into the woodwork now..... Sorry for interrupting your thread.

Hey, no problem! You're lucky to have one of the RS-232 models. Much easier to interface with modern equipment.

Tom L

[marty]

Hi Tom L
I will suggest some things that you can check before sending the board back to Geoff, Most of it is elementary, But that is what usually can trip one up...
trade the 6850's and see what that does, also check for bent pins--
check all Ic's for bent pins..
check that all the resistors , diodes, caps and transistors are in the ccorrect holes and well soldered on both sides...
check that you have it wired right between the jumpers and the connector ( signal table for tty)
switch port 0 to an rs232 and wire accordingly and see if it works as an rs232. then get it to work as an rs232 or if it works switch it back to tty...
that's all I can think of for now....
THANK YOU Marty