Got a call from a man with a 32" Trinitron....its not HD, but it has progressive inputs so I figured I'd give it a whack.
Set doesn't power on. A high pitch whine is heard which lowers in intensity and pitch until silence. This immediately screams short circuit protect.
I removed the dust/tar mix (the whole family smokes...yuck!) and removed the mainboard and took it home. (we agreed that the set itself was just too much of a PITA to load in the car!)
Out comes the multimeter where I find a shorted horizontal output transistor. The base lead has a cold solder joint.
All the fusible resistors are good and well within spec. I do not have an ESR meter but the lytic caps behave as expected when measured with a multimeter. No crap caps, its all Nichicon and Rubycon. All diodes check out as well.
Now the question is should I blindly replace the HOT and make sure the joints are repaired or is there something more sinister lurking about in this set?
Set doesn't power on. A high pitch whine is heard which lowers in intensity and pitch until silence. This immediately screams short circuit protect.
I removed the dust/tar mix (the whole family smokes...yuck!) and removed the mainboard and took it home. (we agreed that the set itself was just too much of a PITA to load in the car!)
Out comes the multimeter where I find a shorted horizontal output transistor. The base lead has a cold solder joint.
All the fusible resistors are good and well within spec. I do not have an ESR meter but the lytic caps behave as expected when measured with a multimeter. No crap caps, its all Nichicon and Rubycon. All diodes check out as well.
Now the question is should I blindly replace the HOT and make sure the joints are repaired or is there something more sinister lurking about in this set?
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