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James Sweet James Sweet is offline
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Default JVC television - foldover at top of screen


"Peabody" wrote in message
...
I have JVC model AV-27920 television that goes back a few years.

A few months ago, I began having a problem at the top of the screen.
It's hard to describe, but it looks like to top part of the image is
folded over and displayed upside down. I guess it looks like the
the vertical isn't quite making it all the way to the top before the
lines start being displayed.

At first this occurred only when the TV was first turned on,
affecting the top couple inches. As the set warmed up over 10
minutes or so, this would gradually shrink, and finally all
disappear, and everything looked normal. Nothing strange happens at
the bottom fo the screen.

Now, the foldover when cold covers more of the screen, and it no
longer goes away completely when warm.

I actually have the Sams schematic on this from folder 4080, and I'm
hoping that whatever is failing is something I can replace. An
electrolytic maybe?

I don't have any test equipment, but am competent to remove, test,
and replace things. So perhaps someone can suggest what to look
for. I would appreciate any educated suggestions, either in general
or with reference to functions I can find on the schematic.

Thanks very much.


Electrolytic capacitors around the vertical output IC, they'll be smallish,
probably 1-10 uF at about 50V and usually there will be 2 or 3 that need
replacing.