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#16
12-28-2009, 06:54 PM
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On a hunch (the guy said it would evenually start and then be ok) that the recent cold weather may be an issue, I got out the heat gun and began aiming it around the board. At 1st no joy so I started different spots and then tried it again. This time I heard the very distinctive degaussing noise and pop the screen comes alive.
 So now I have to check some stuff out. I have a funny feeling it may be the silly variester that may be part of the deguassing. Anyway at least I have a plan. I will try a few more times to see if I can isolate the spot that needs the heat. 
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#17
12-28-2009, 07:31 PM
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turned it off, would not come on, tried spot heat, no joy, I can see this is going to take some time....
re heated the whole back and got it going again. argh... well at least I CAN get it started. gotta find the part that likes the heat. I did try shooting cold spray all over, no effect. I will just have to keep at it.
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#19
12-28-2009, 07:44 PM
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My dads panasonic was doing the exact same thing. It was touch sensitivity as well as heat sensitive so it is most likely a cracked solder somewhere. After hours of looking I came to the conclusion it had to be one of the connections under one of the BGA mounted chips.
He wanted one of those new led flat screens and the power consumption was half of that big crt so I told him go for it. This new lead free solder is such a bunch of trash.
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#20
12-28-2009, 08:02 PM
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well maybe getting close, after severl trys I aimed it at some caps (look like polyfilm) near by the flyback, heat there and it came on. Good point about the solder, I will examine that area closely, will also try pushing around that area to see.
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#22
12-28-2009, 10:03 PM
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got to give it a rest, I cant seem to isolate it to a specific part, but there is a rather large value electro cap right in the trouble area (very close to the flyback). I cant tell the value, but a guess is a 500-1000uf cap.
I dont know if a cold cap could be diff than a warm cap (leaky/open) but its not hard to get at so will do that one. I will have to be careful about polarity, cant see from the bottom any markings and will not know from the top until I get it out, so will be sure to note the way it is in now. It does have the built in digital tuner, and I must say the pic is excellant even with the cheap rabbit ears, but it will not pic up channels that my DTV converter gets just fine with the same set of rabbit ears. Oh well that will be the next issue if I ever get this thing going. Getting late time for "tombs of the blind dead" (dvd I got for Christmas), good stuff IIRC have not seen it in over 25-30 years... last nite it was planet of vampires, boy did allien rip that one off big time. I hope they paid some kind of royalities...
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#24
12-31-2009, 03:25 PM
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ok, seems one of the codes (3) had to do with a xray warning
 I tried reducting the HV till it cut off, then turned it back until the pic was just normal. turned off with the remote waited 10 seconds turned on. maybe I am on to something here... If they replaced the fly (as they claim) and did not reset it right maybe that is the issue? Still dont know why the heat would effect that.
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#27
01-01-2010, 03:14 PM
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BINGO!!
check yet another cap near the heating point, a little 25uf job. not leaking but had to turn the power factor all the way up on the cap checker. replace it and it works perfect. Just for grins I put the bad cap on the tester, leave it hooked up, heat it up, an sure enough it value changed some, but the power factor was able to be cranked way back for max eye opening. anyway now I can watch the gators on my NEW to me TV
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#28
01-01-2010, 03:38 PM
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in my internet searching I found this a common problem, I wonder how many TV's get trashed (not to mention people getting repairs they don't need).
It also make we wonder about the wisdom of shot gun replacement of old caps that are working and test fine with new ones. I mean the old ones are 40-50 years old and sometimes test fine (talking electrols here). While these were only 5 yrs old. I also wonder if it has to do with the tiny sizes they are made, and the life expectancy of "modern" consumer grade electronics.
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#29
01-01-2010, 04:03 PM
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Talked to the guy that gave to to me, he said the orig proposed 300$ fix was to replace the whole board, yep that would have done it since the cap was on the board, sorta like replacing the whole engine because a spark plug is bad. He was going to take it home, but they insisted they could fix it for 200$ but he had to wait 3 weeks for the parts... oy vey... then he got it back worked for 3 days and then same deal and oh yea no warrenty at all.
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#30
01-01-2010, 05:31 PM
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You'd be surprised at the number of TV's that have come to me from repair shops that told the owners that it couldn't be fixed, would need a whole board, or would cost five fortunes to repair. Many of said sets only needed minor repairs. Either the shop didn't know what they were doing, wanted to make a killing, or had the customer pegged as a deadbeat who probably wouldn't pay.
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