FREE BEER!
bump.
The tube forum moves very fast so I'm bumping it to the top of the list again hoping someone who can help spots this.
No Australian can resist our traditional cry for help. I'm serious too, I'll phone your local to buy you a jug of your favourite.
The power supply has:
two 6.3V filament supply outputs,
50mA 0-250V
a variable current 200mA 0-400V output.
the 0-400V section is faulty. the getters in the driver tubes for that section look ok, the filaments all light up.
With only one tube plugged in (I tried all four in turn) it doesn't work.
no output at all.
There are a couple of ICs inside, they are very old looking comparators. I swapped them over, assuming one is for 250V and one for 400V, and it still didnt work. At least I know both comparators are ok.