Ah ok. So that first transistor on Q6 serves as a chopper to double the
DC voltage up to 360v when using 120. When you reconfigure the jumpers
for 240 you basically bypass that thing.
I have 240 in my shed so I'll start by seeing if there is 360v on the
input rail. If not then I'll re-jumper to 240 and see if it appears
then. Then trace everything forward from there....
C
On 9/13/2021 1:22 AM, J. David Bryan via cctech wrote:
On Saturday, September 11, 2021 at 21:31, Chris Zach via cctech wrote:
Ok, thanks!
You're welcome.
I just tried mine again, it's a dud so I am going to have to figure it
out. First step was to see if the rectifier had any voltage so I
disconnected the + side and checked it with a voltmeter. With 120v
plugged in I saw 200v DC which is probably not too far off. That seems
to go to the inverter card, which I don't know what it's doing with
that.
There's a reasonably complete theory of operation of the "B" power supply
(which is what you have) in section IXB of the HP 1000 M/E/F-Series
Computers Engineering and Reference Documentation. There were several
revisions of the "B" supply, but they all used the same motherboard (as far
as I know), so the various plug-in card functions would be pretty much
equivalent across versions.
Is there a block schematic of what does what on this PS?
Page IXB-6 of the above manual has one. There's also a troubleshooting
flowchart on page IXC-3. Section IXC is specifically for your supply
version and has the appropriate schematics, but the theory from the earlier
"B" supply should be broadly applicable.
-- Dave
