OK, has anyone any ideas about the failure mode behind this? - the two attached files are the top and bottom views of one of the PCB's from inside a Sharp TV LCD panel.
The opposite ends of the tubes have individual connectors up to the inverter board, but this end simply links pairs of tubes in series.
As you can see from the pictures, each socket has three mounting points, only ONE of which is actually used. So how come the burn-up happened at a joint that has no possible current going through it?.
This isn't the first one I've seen like this - and the burn-up is probably my fault, running it in pieces with the trip circuit disabled - but there's no real option, these specific sets commonly fail with 'tube errors', but these are usually VERY intermittent (this one's been running disassembled for over a week).
Incidently, I noticed it had failed by a slight burning smell. and on checking I noticed one tube had gone out - so even though the tubes are in series the other one still worked. When I removed the tubes, the faulty one actually snapped off clean at the end.
At least you can get the tubes and boards for these Sharp sets, good job because complete panels for Sharp cost 3-4 times the price of the set!.
The opposite ends of the tubes have individual connectors up to the inverter board, but this end simply links pairs of tubes in series.
As you can see from the pictures, each socket has three mounting points, only ONE of which is actually used. So how come the burn-up happened at a joint that has no possible current going through it?.
This isn't the first one I've seen like this - and the burn-up is probably my fault, running it in pieces with the trip circuit disabled - but there's no real option, these specific sets commonly fail with 'tube errors', but these are usually VERY intermittent (this one's been running disassembled for over a week).
Incidently, I noticed it had failed by a slight burning smell. and on checking I noticed one tube had gone out - so even though the tubes are in series the other one still worked. When I removed the tubes, the faulty one actually snapped off clean at the end.
At least you can get the tubes and boards for these Sharp sets, good job because complete panels for Sharp cost 3-4 times the price of the set!.