On 3 Oct 2005 12:09:16 -0700, "onyxx" wrote:

Hello, i am working on a 15 inch color monitor. I have a 150W light
bulb connected and when i turn the monitor on, it starts to pulsate for
about 10 seconds at 2hz(+-)So it pulsates like 15 to 20 times and then
it stays at normal brightness.

If it is at normal brightness...

During all of this the monitor is NOT
connected to a PC, but when i do it statrs to pusate again but this
time indefenetly. I´ve tried changing the refresh rate and this causes
the pulses to speed up, so if i go from 800x600/50hz to 800x600/60hz,
the pulsating goes from about 1hz to 2hz and if I pull the VGA
connector the pulsating stops. Should i try a bigger light bulb?
I also get over 1000Vdc (DMM goes blank)both at the chopper
transistor´s and HOT´s drain pin.

....it is no wonder that the DMM is complaining...if only I could
remember what "drain" means...FET terminal...equivalent to collector
or emmiter? Can't remember...if emitter, something weird is going on.
Hmmm.

Tom

What controls B+ voltage? is it
just the HOT or is there a voltage regulator somewhere?
I am looking for a bad V regulatro or maybe a bad resistor somewhere,
Am I in the right direction here?
Thanks.