Hopefully get back to this one tomorrow.
Working at 2/3 mains coltage but temp of the chopper transistor goes too
high, if I let it, and power consumption goes well above 20W.
Looks as though something has gone wrong with the mark/space contol.
It slowly increases so the "5V" line goes 2..3V and then jumps to 5V with
equal mark/space which is presumably not necessary.
I will check there is no excessive load on the +/-18V or 5V rails despite
all functions working as far as front panel display.
I've not established the function of the feed forward optocoupler from the
main processor board to mains side of the ps


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Diverse Devices, Southampton, England
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