Successful TV repair

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This Sharp 22-inch widescreen was as dead as Dillinger, but that's not a bad thing as it usually means the power supply has gone which is easier to fix than a backlight inverter. After checking the obvious things that might be a problem including the fuses and the ON/OFF switch I took the power board out. A quick search online revealed (as usual) a common failing, not bad capacitors in this case, but a failed diode. There were 3 large, high current (5A) diodes on the board wired in parallel and after unsoldering one leg of each diode from the board I was able to test each one and right enough the middle one was shorted out. A lot of searching of old boards yielded up a 4A diode at a slightly higher voltage rating which I figured would do as a replacement to test the television, so I soldered the 2 good ones back in place and replaced the bad one. With everything back together the set works a treat, especially with the Freeview HD box on the right which can power an amplified aerial I had lying around. When I get time I'll mount the antenna on the outside of the workshop.

A handy feature is that the television can record programmes to a USB pen drive with scheduling right from the programme guide (EPG).

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