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[email protected] pharkus@pharkus.homeip.net is offline
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Default Sony KP-43HT20 - I do not believe my convergence ICs are atfault.

On Dec 17, 2:03*pm, Meat Plow wrote:
On Wed, 17 Dec 2008 03:55:58 -0800, "William Sommerwerck"
wrote:

The ICs could be bad, drifting as they heat up. But I don't blame you for
not wanting to perform what appears to be a shotgun repair.


The convergence ICs are the hardest working parts in the set. It's
been my experience that when they go that's it. And depending on the
design they *blow fuses and/or smoke resistors.

I would rule out other problems before replacing these chips.


Based on what I've read so far, this set is of such a design that it
blows a set of 3.15A fuses that look like yellow resistors.

All such fuses are good.

After re-soldering the IC, it ran for about 5 minutes before it flaked
out again. I turned it off and back on, and it ran for another hour
without the major problems, until I got tired of watching it and put
it away for the night. I haven't tried it again today yet.

During that hour, it appeared that the red image was slightly larger
than the blue and green images - ie, it was converged at some point
nearish the middle of the screen (although, interestingly enough, not
the exact center), and there was red to the "outside" of everything. I
can't explain this too well, I guess, but "it looked like the red
image was bigger than the rest" should give a good idea.

I know nothing about the history of this TV, so multiple problems are
a possibility. After power-cycling, it ran fine for long enough that I
actually got tired of watching TV. My next guess, on the "total loss
of convergence" problem, is one of the four electrolytic capacitors in
front of the IC. They're cheap enough that I'm just going to replace
all four. I believe, however, that the "red image is bigger" issue is
a second, unrelated problem? Possibly even more mechanical than
electrical? I definitely need some guidance on this one.