1-to solder vertical integrated circuit 2-see if any electrolitic filter is blow up-or 3-verify +24vcc 4-replace all electrolitic-filters.
Hello! What you're describing sounds like a vertical deflection problem if it also occurs when you're watching a TV program. This type of trouble is a component failing in the vertical circuit of your set. A loose solder connection could cause this. On the other hand, if it just happens when you run the VCR, your problem could be somewhere in the tape drive mechanism or possibly a bad tape. Things like slipping clutches,bad belts sticking guide rollers are a few things that will cause this in a VCR. You need to have a tech check it for you. Hope this gives you some help. Stargazer
SOURCE: Pictures shrinks.. Panasonic TC-20LM Television
Shrinking picture is a voltage regulation problem in the switch mode power supply, Possibly a cap used in the feedback circuit. Or an over current condition on the B+. This is a very tech intense repair because there is no magic bullet. If it is shrinking on bright scenes then you can bet it is a regulation problem, bright scenes draw more current from the power supply causing this effect. I would not suspect the horiz output because the regulation for this circuit usually comes from the main switch mode power supply. One diagnostic is to monitor the B+ going to the horizontal output and see if it fluctuates. If so you can bet it is a cap or optical coupler in the switch mode circuit.
SOURCE: Old Panasonic tv approx 10/12
The main coupling capacitor feeding the frame scan coils has failed or the output stage on the frame stage has failed due to dry capacitors or dry joints.
Fault finding and components are not a problem and yes it is very repairable. Any technician that knows how television works can repair this standard frame output stage.
I hope you find a good technician.
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