30 Dec
2021
30 Dec
'21
1:32 p.m.
Sounds like you're testing things basically the way I was:
http://www.glitchwrks.com/2019/06/05/pdp1110-psu-repair
I used a large Stancor 24 VAC transformer to supply power to the modules, since they
usually see 20-30 VAC from the big transformer in the chassis.
For dummy loads, I like automotive tail lamp bulbs. Series/parallel as necessary to get
the load you want. Do keep in mind they get hot enough at rated voltage to melt soft
plastics.
I replaced them with a LED and a resistor.
Many of the later modules do that anyway! I used incandescent lamps because I had them on
hand. Wouldn't you know, after reassembling and a few hours of bench running in the
PDP-11/10, one of the old ones I hadn't replaced burned out too :P
Thanks,
Jonathan