Can someone
help me understand these old HP schematics?
I see the 15 adapter pins shown at the top right of the
page, and see where one of the pins (# 5) appears to go
to something labeled EIA IN on the "Logic Mother Board"
FWIW, 'EIA' was commonly used at that time (particularly by HP) to mean
what we'd normally call 'RS232;
section. Some pins (3, 4, and 6) appear to not
be
connected to anything. Most of the others seem to go
to the Analog Mother Board, but I am not sure how to
follow them from there. What would be nice is if I
Given the one sheet of schemaatic that I've seen, you can't. You need
detailed schematics of the motherboards to trace the signals to pins on
the plugin cards (I assuem) and then scheamtics of the approprtiate cards
to see where they go in the 'real' electronics.
Do you have that information?
I have spent a little more time looking at the information that I have. My documentation
does not include detailed board schematics. However, these boards do not look extremely
complex. I have figured out how the pins on the interface are numbered. The top left pin
is #1 and the second (lower) row contains pins 9 thru 15 (left to right). I have followed
these wires from the adapter to the board, where they are connected. At the point of
connection, there is a number like 901, 902, 905, etc.
I also found a page in another manual that shows how to hook the interface cable to an
ASR-33. It has an "in-line" molex style adapter. I need to look at that
connector on the ASR33 and see how many wires it contains. Tony probably knows that
answer off the top of his head.
It's suppertime. I'll do more digging later. I also will photograph the boards
that these wires run into on the plotter.
Ashley