micro pdp11/83 power supply

allison allisonportable at gmail.com
Sun May 13 08:18:38 CDT 2018

On 05/13/2018 01:51 AM, Waldemar Brodkorb via cctech wrote:
> Hi,
> I started to revive an old Micro PDP11/83 I have for over 12 years
> now. It is fully assembled and last time I tried to start the
> machine it some kind of started.
> My biggest issue at the moment is the power supply.
> After the machine is running for a while, let's say 10 minutes and
> then when I poweroff, the power supply starts producing a lot of
> dense smoke. The smell is very penetrant.
> What can I do with the power supply? Do I need to exchange it
> completely or just parts of it?
> At the moment I removed it from the case like described here:
> http://www.bitsavers.org/pdf/dec/pdp11/microPDP11/EK-MIC11-TM-002_MicroPDP11_Systems_Technical_Manual_Sep85.pdf
> Thanks in advance for any starting hints,
>  Waldemar
Make sure the cause is not the cable from the PS to the Back plane. 
Inspect the plugs for burnt
for signs of over heating.

There were two versions of the cable on had all the wires unequal length
to make the bend pretty,
the preferred one has all the wires equal size.


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