I have a Tally 420PR paper tape punch mechanism with no
electronics, and would like to build a driver board for it. I have
a DEC PC8E (M840) interface card for my 8/A project which would be
the logical starting point. I was able to find a schematic of the
punch online but no other manual or information.
The solenoids run on -48VDC but I have no data as to pulse widths
and duration, or even the speed of the mechanism (30cps?) There
are solenoids for each of eight (data) punch pins, a sprocket-hole
punch, tape feeder (which also operates a contact to actuate the
forward ratchet mechanism), and reverse ratchet (for rubout I
assume).
Any ideas? I am not sure how much of the timing is generated by
the M840 card and how much by the M710 inside the PC04 assembly.
Also, the connector is a Continental 25034-16P. Does anyone have a
mating female connector?
thanks
Charles