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Discussion Starter #1
Hi all.

About two weeks the TV started exhibiting fluctuating sound levels, then quite quickly the picture started getting all kinds of lines/waves that made it pretty much unwatchable. If you unpluged it, it would go away for a short time but eventually it returned and got worse. The final thing on the screen was something akin to "northern lights" as blue, green and red liines came up from the bottom of the screen in the shape of a mushroom (cloud!) and then eventually nothing, which is where we are at today.

I've done a fair bit of research, downloaded the service manual and have the set open and ready for business. Now I really just need to know where to start. Here are a few more things that I have done
to make things easier. First, I can hear the tv powering up...u know that static sound that happens when u hit the power button only nothing else happens after that. Upon plugging it in, u get 3 green flashes which according to manual is "indicating the Microprocessor has initialized and is functioning
properly." I've tried to get the error code and it reports "12" which means, everything is just peachy! (no error has occurred) . I've tested all the fuses for continuity and all appear to be fine as well. I've checked all capacitors visually and none of them seem to be bulging so at least on the outside, they seem fine too. The final thing I might add is that (not sure what you call it) the tube that looks like an old vacuum tube somewhat, basically the very bottom part of the whole lighting assembly does glow very slightly when the power is turned on. The lenses give off no light and like I said, no video on screen to speak of.

I hope that has been descriptive enough to get some pointers. Now I just need someone to point me in the right direction and away we go.

cheers
Tony O
 

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From what you described, the power supply and likely high voltage are up and running and the filaments are lit. The set will require troubleshooting at this point that is beyond the scope of this forum. This would include checks to see where voltages are present or missing, whether the unit has any raster at all, and perhaps signal tracing. This is all beyond simple symptom-repair relationships that are practical in forums like this. Checking capacitors beyond the visual that you have already performed may require capacitance and ESR tests, as well as power supply measurements and perhaps observation of the supply lines with a scope.
 

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I was afraid you would say that. I was hoping it was just the convergence thing that I keep reading about. I'm more than happy to check voltages, I'm just not sure where to start. One other thing I didn't mention is that there is some gold colored sticky stuff that has dripped from the lamps onto other components. I guess the best thing to do is post a picture of this.

thanks for your help thus far.
-Tony
 

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the plot thickens...

Just a half hour ago, if I adjusted this thing here:

http://www.santacruzbiofuel.com/gallery/view_photo.php?set_albumName=TV-Pics&id=tvPics_002

it says "focus" on one row and "screen" on the other. If turned up the "screen" colors the lights came on (b, r, g), not sure what that means. Pic of lights ON!

http://www.santacruzbiofuel.com/gallery/view_photo.php?set_albumName=TV-Pics&id=tvPics_003

Then after a bit, they stopped. I powered up again and this time, the tv would come on and power off in 2 seconds. I could hear it "click" and eventually found what was clicking. It's this thing here:

http://www.santacruzbiofuel.com/gallery/view_photo.php?set_albumName=TV-Pics&id=tvPics_006

the thing that says DEC here. It seems to me something is causing a short. Could it be the DM board? (i've read this might be the problem on other forums).

btw, I realize this might very well be beyond the scope of this board, but it seems to me that because the sound doesn't work either, that the culprit probably isn't as complex as it might seem.

cheers and good weekend.
-Tony O
 

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I was afraid you would say that. I was hoping it was just the convergence thing that I keep reading about. I'm more than happy to check voltages, I'm just not sure where to start. One other thing I didn't mention is that there is some gold colored sticky stuff that has dripped from the lamps onto other components. I guess the best thing to do is post a picture of this.

thanks for your help thus far.
-Tony

That sticky stuff is a serious problem and has to be handled carefully and completely or you will have more serious problems.

http://www.hometheatershack.com/for...rt-based-rptv-coolant-problems.html#post67460
 
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