[GreenKeys] SB-2244 TTY patch panel

[Jim Haynes]

Some implementations of Teletype with crypto equipment required that the
stepping the Teletype keyboard or tape reader at a fixed rate.  In the
Model 28 parts books you'll see mod kits to adapt things for "synchronous
pulsed operation".  A large station might have a TD stepper facility
consisting of a baud rate generator and then a bunch of boxes that
send out TD stepping pulses to all the TDs.

I don't know why it was this way.  I don't have any first-hand knowledge
of crypto equipment, but I did once buy some TD stepping equipment at
a surplus sale.

Where this is done each TD or keyboard has to have its usual loop and
then a loop for the stepping pulses.  So I'm guessing what you have
provides for switching both the signal and the stepping pulses.



jhhaynes at earthlink dot net