4 Dec
2013
4 Dec
'13
9:16 a.m.
1. I believe you should look at page 602 of the PDP8/A users manual:
http://bitsavers.trailing-edge.com/pdf/dec/pdp8/pdp8a/EK-8A002-MM-02_PDP8A_…
2. Maybe. However if your chassis is set up for remote power control you
need to short pins 1 and 3 of the 3 pin control cable connector. Then the
power should be controlled by the power switch on the limited panel.
However, your model (8A420-CN) is originally set for 240VAC (see page 34 of
http://bitsavers.trailing-edge.com/pdf/dec/modules/modulesAndOptions/Option…);
you might have to adapt it to 120.
3. G8019 doesn't show up on the price list; don't know what that is.
Good luck bringing up a 8/A without the programmers console. Without it
you can't toggle in anything; you're limited to whatever boot devices are
programmed into the boot roms on the M8317.
Marc
On Wed, Dec 4, 2013 at 3:46 AM, <anders at abc80.net> wrote:
Hi,
I have started restoration of a PDP-8a model 8A420-CN. I doesn't have any
schematics for this machine and I have searched internet for sources
without any luck. The sets on
http://bitsavers.trailing-edge.com/pdf/dec/pdp8/pdp8a does not include my
version.
My machine came with 16K*12bits core memory, 20 slot backplane and only
the "Limited function board" frontpanel (don't now if this machine ever
had the "Programmer's console").
This is how my "Power distribution board" looks like:
http://www.abc80.net/docs/pdp8/pdp8a/DSC_2118.JPG
Some questions:
1. Is there anybody that could help me with schematics on this machine?
Scans are preferred, but I can pay for paper prints. I'm especially
looking for a diagram that matches the "power distribution board" that I
got.
2. If I plug in the machine with only the regulator boards (2xG8018) and
the limited function board in it, should the lights and fans come to life?
3. I suspect that my model shouldn't have "Power distribution board
control", G8019 since my "Power distribution board" misses the connector
for this board. Can that be correct?
Any help is appreciated. PPD-8a is new to me, but I have some knowledge in
the PDP-8 architecture since I restored a PDP-8/L that was in really bad
shape.
/Anders
