20 Apr
2004
20 Apr
'04
4:26 p.m.
Hi Tony,
It would appear that you are correct. Once I removed the cover, I could clearly
tell that the "chirp" is coming from the switching power supply. There appears
to be no activity from the rest of the monitor, including the fact that even
with the lights off, I could not observe filaments lighting. The power LED does
It's not unheard-of for the CRT heater to run off the flyback
transformer. So if the horizontal output stage is dead, there will be no
heater glow.
light, however it's fairly dim - I don't know
how brightly it would normally
light.
The final filter capacitor in the supply is rated at 180v DC. I powered the
supply briefly under no-load and the output rose to 140v. With all the
connections in place, it is producing about 55v - I have no idea what the
normal requirements of the monitor are.
I would guess around twice that voltage at least. Does the PSU have one
output or seceral ? Have you checked if any of them are stuck at 0V?
-tony