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Update.
Horizontal transitor (C5129) showed a short between base and emitter (short in diode mode and 0.4Ohm in resistance mode). I took it out but the transistor is fine.
I inspected the PCB and I see the Base is going back to ground via a small transformer (labelled T701). This small transformer reads indeed 0.4 ohms on my meter.
BBut I believe this is normal?
Removing the Yoke plug did not improve things.
I took out the main switching transformer to understand how many voltages are generated. I counted 5. I can follow them on the back of the PCB, they all go through diodes and capacitors (obviously!) and then disappear around the board. I tested all I could think of but I did not find a short.
I've removed a connector which seems to take filament voltage and 12V to the neckboard but nothing.
The outputs sometimes go through transistors and voltage regulator but, again, I don't see a short there.
Any other ideas?
I might want to inject some voltage on the various rails to see if by any chance my thermal camera sees something?
I have a twin board which - surprisingly - is showing the same fault, I could use that one.
Thank you!
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