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Discussion Starter #1
I have a rather odd issue with my Panasonic that I just simply cannot find the right information to make me feel all warm inside. I am an avid DIY'er with enough experience to strip search my TV but not before I find reasonable information to make me feel it would be necessary.

The televisions convergence is creeping out of whack nearly every couple days. I have full controls to return it each time but it doesn't stay for long. The extreme corners seem to be slightly warped in color regards. The screen as a whole seems out of focus as well. And as an added bonus the screen height and width is off the screen by about an inch all the way around. I imagine that specific issue could cause the focus problems.

I have already reseated all the cable connections on the board in the back as well as inspection of components but nothing seems to be amiss from what I can see.

I have already read through the service manual so I know the service menu is an option but I know its never been messed with which would lead me to believe its a physical issue and not just settings.

My next step was going to be swapping ICs but I feel since I have full control of the convergence settings the chips should be okay right?
 

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STOP! Do not jump to conclusions that your problem is convergence. If you can adjust the convergence your ICs are fine. The fact that your focus and image size are off indicate that you have a power supply or high voltage problem. Test the output from your power supplies very carefully. Do not attempt to measure high voltage unless you have the proper probes and experience. You can tell if you have a problem in the flyback by monitoring the primary and secondary voltages in many cases.
 

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Thank you so much for stopping my ignorance to the issue at hand. I guess now is not the time to express my fear of high voltage! Should I follow the service manual to the letter or do you have an experienced method that the manual won't explain?
 

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So I have combed though the service manual several times before even taking the back off of the PTV and already I think there is an issue. Everything refers to pumping a signal into the TV while testing all necessary circuits. It also provided a part# to said device that would accomplish this however it seems this NTSC signal generator is not available, at least not the one they are referring too.

All that said is there something else i can do to achieve this display for testing?
 

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I am recalling that we had to have the TV serviced awhile back due to something with the HV. This originally was a Rent-a-Center purchase and the warranty we had covered the repair. The TV one day didn't turn on and simply displayed an LED code that is described in the manual as a +140 error. Is it possible the service replacement was not followed up with proper screen tuning?

Also another symptom I didn't mention was the screen surges somewhat and by that I mean you can see the screen expand in overall size by about 1/4 of an inch and become brighter for short bursts at a time. That is my best description on the matter.
 

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It really sounds like you have a regulation problem. Look for a swollen electrolytic cap or a bad cap in the flyback circuits.
 

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Discussion Starter #8
This is sounding very promising. This weekend we are stripping the TV and benching it. I'll start by looking for physical anomalies first. I'll pay close attention to the HV and fly back circuits.
 
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