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Panasonic tv doesn't have picture

Hi, My tv has stopped working. The symptoms are as follows,

Recently I noticed that the picture requires ever longer times to start after switching the tv on. The sound comes on immediately. I new that eventually, the pictures will not come on, and now I have reached that point. It seems as though the picture cannot "complete" the "warm up" stage. The screen is completely dark, i.e. as if there is no power. I have checked all the controls, and it is not a brightness setting or the tv/vcr switch, I am sure of that.

The model is Panasonic TX-W28R3

I am guessing that this is due to some dried out electrolyte, but this is just my educated guess, due to the fact that the fault became progressively worse, which could be an electrolyte in the process of drying up.

If anyone has any experience with this particular model, please tell me what is the part, and I will fix this in a flash.

Thanks B.Eng

Reply to
info
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It may be something to do with the CRT heater supply, which could indeed be due to bad electrolytic caps, or bad solder joints, especially on the CRT connector.

I take it you are skilled in electronics and are aware of the potential lethal dangers within a CRT TV? First things first- check the neck of the CRT glows. If it does, the set will need some skilled diagnostics to get any further. If it doesn't, the fault should be easy to find as there are few parts to go wrong in the heater supply on most sets. Usually it will be a bad solder joint or broken PCB track.

Dave

Reply to
Dave D

Dave, I know about the dangers (I have a diploma in EE). When you say it may be a bad solder/track, this does not explain why the problem got progressively worse. A bad solder/track usually causes an intermittant problem?

Reply to
info

Yes but a CRT heater has a lot of 'thermal inertia' and takes a good few seconds to go from off to on, on to off. A bad connection can often become a good one once parts warm up and expansion sets in. With ageing, thermal expansion and contraction and some arcing, a worsening connection can be fully expected.

However, I agree the most likely cause is thermally sensitive components, especially electrolytic capacitors.

Dave

Reply to
Dave D

Reply to
Papa_J

Thanks, but I'm not asking the question, 'info' is the OP!

Dave

Reply to
Dave D

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