Hello There,
I have a SONY MONITOR (PVM-20M2MDE)
First fuse was blown and chopper(2SD1878) was destroyed. I replaced the
chopper and it destroyed again (anything else around was fixed,
checked OK).
I had to open the chopper and see the horizantal drive signal, it is
only 5 KHz which certainly is too low for FBT to tolerate. I replaced
the horzantal IC (upc1377c) and the signal is still the same.
Here comes the headache ... there are a lot of feedback paths from FBT
to this IC, which affect the frequency, I can't connect the chopper (to
have feedback)as certainly it destroys again.
Has anybody experience with such a problem ?
I should add that the destroyed choppers had all pins shorted (this
usually means an error in drive circuit).
Any help will be appreciated.
Dario.