pumping noise from PSU in TV

Hello,

I always thought I'm a professional R&TV-Technician, but I'm slowly running
out of ideas:
I have here a Provision 14" TV portable, Type "ST-1410T PAL BG Black".
The only ID I'm able to find on the PCB is a codelabel on both rear case and
tuner, reading 938842.82832
I checked the horizontal and vertical driver stages, all OK, the CRT PCB is
also intact, but still the PSU generates a chirping noise, about 4 chirps
per second. When switching the set off the LED shows for a half second to
be pulsing in the sequence of the chirping.

Any Ideas, recommendations?

 

Something's still shorted, have you checked all the diodes and capacitors in
the output section of the power supply? You could also remove the rectifier
diodes one at a time to disable that output, that'll narrow down which one
is overloaded.