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hitachi 46ux13k chassis ap33 no picture

I got this chassis AP33 the original problem was, it had a good picture but when you fi rst turned it on, the picture rolled, had horizontal tearing, and jittering, along with the PIP not functioning at all. after it warmed up, the picture would tear and jitter a little bit. almost like watching an old VHS.

So, I read that the PIP board and 3-line board have bad caps.

First, I recapped the PIP board, and my pip came back. perfect pip, but now my tuner died. snow.

anyway, it still had the tearing and jittering, So i removed the 3-line module.

I seen one cap in that module where it was so bad, it eaten away part of the board and traces. So I carefully removed that capacitor, and traced down that board, wired a new capacitor in. replaced all other capacitors the same way I did the PIP board.

Now, I stuck the 3-line back in, whoops, I got sound, I got OSD, i got no pic. :-(

I checked and doublechecked that board over and over. I dunno what went wrong. no picture.

am I foced to replace that 3-line? where do I get one?

Reply to
Mike
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one of them stupid STK4274s is out in it too I noticed. there is no green correction and that part of the heatsink stays relatively cool.

So, I replaced it, and still doesnt have any green correction, but this time the green STK gets too hot to touch in the matter of seconds, with or without the conv yoke connected. rather odd, unless i got a dud STK.

any ideas? S-video works, so thats a good sign my comb is shot.

Reply to
Mike

Did you check the Pico,s maybe one is open ?

Reply to
kip

I found 2 2.2ohm resistors that connect the ouput of the STK to the yoke, its open. Im going to have to order some replacements.

Reply to
Mike

i dont think any fuses are open, as red and blue convergence is ok.

Reply to
Mike

your missing either -28 or + 28 volts feeding the convegance amp you replace most likely the - 28 with out the bias it will fry the amp again look for one of the protection pico fuse open..

Reply to
David Naylor

I just noticed after double checking and triple checking the Y/C seperator module, I installed a new coupling cap on the YCE pin backwards. im sure that wouldnt cause a totally black pic, but you never know.

what is YCE anyway. its got Y out, and C out, but whats YCE?

Reply to
Mike

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