Speaking of IBM, Schematics for a ps/2 P70 power supply??

From: Greg Linder <glinder_at_ews.uiuc.edu>
Date: Sat Jun 22 12:51:03 2002

        I liberated a plasma display ps/2 p70 from a friends garage- It
does the typical power supply thing where it comes up for a bit, and then
konks out. I took it out of the machine, and have pretty much made sure
the power supply is broken- I have tried loading the DC outputs with my
bench load IDE drive, and it comes up and goes down again, unless it is
expecting a load on the plasma screen power connector. I am a power supply
newby. The supply only turns on long enough to get the fan to go about 1/2
rotation, and the dies again.
        This gets kind of tricky because I have never managed to fix a
power supply, ever, I usually just find a spare from the bin and pop it
in. However, I don't have a spare that will do whatever voltages the
plasma display requires, nor do I have a supply that is even close to this
form factor.
        It appears from my probing that at least the filter caps are good-
I am getting a pretty stable ~160 volts DC across two separate large
filter caps, which seems a bit big, but I have not learned enough
analog to have a clue how this supply does what it does.


        Thanks for any assistance,

                Greg Linder
Received on Sat Jun 22 2002 - 12:51:03 BST