NotTaR of Television Sets : Older TVs with multiple intermittent pro..  
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Older TVs with multiple intermittent problems

If the set is say, a GE, with a manufacturing date around 1980, it is possible you have one of those circuit boards best described as bad solder joints held together with a little copper. In this case, prodding may get the set started. The circuit boards in these sets were double sided using what were called 'rivlets' for vias. The rivlets were relatively massive - literally little copper rivets - and they were not adequately heated during assembly so there were bucketloads of cold solder joints that showed up during middle age. I repaired one of these by literally resoldering top and bottom of every one of the darn things with a high wattage iron.

TV has burning smell

Assuming there are no other symptoms:

If this appears after extended operation - an hour or more - it may just be a build up of dust, dirt, and grime over the years. After understanding the safety info, some careful vacuuming inside may help. Just don't be tempted to turn any screws or adjustments!

Dust is attracted to the high voltage section in particular - even the front faceplate of the CRT collects a lot and should be wiped with a damp cloth from time to time.

If the symptoms develop quickly - in a few minutes or less, then there could still be a dust problem - a power resistor may be heating a wad of it but other possibilities need to be considered.

If not dust, then probably in the power supply but realize that TVs don't have a nice metal case labeled 'power supply'. It is just a bunch of stuff scattered around the main board. Without identifying the part that is heating, a diagnosis is tough especially if the set really does work fine otherwise. However, if a series regulator were faulty and putting out too much voltage, the set could appear to work properly but in fact have excessive power dissipation in certain components. If cleaning the dust does not solve the problem, you will probably need a schematic to identify the correct voltages.

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