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Leonard Caillouet
 
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Default Mitsubishi CS-2655R vertical jitter.

David,

This is not one of the sets that has lots of bad caps. This one is more
likely to have some caps that may be low in capacitance due to age than lots
of high ESR or physically leaky ones. I'd be checking them with a
capacitance meter or looking at the response of the circuit in addition to
ESR checks. Look at the output from the regulators with a scope and see if
they are noisy. Like Bill said, look for any old glue on the board. Some
of these old sets had some glue that dried out and absorbed moisture from
the air after years in service and this would cause some strange symptoms
that have caused many techs to chase their tails.

Leonard

"David Farber" wrote in message
...
I'm not making much progress here. Every cap I've checked has acceptable

ESR
and that goes for the ones I initially replaced. None of them shows any

signs
of leakage. I've scraped off some minor glue deposits in a couple of

areas. The
picture still jitters.

One weird phenomenon occurs when I use an external video input. If I send

a
crosshatch pattern in through the video input, the TV shuts down after a

few
seconds. The same crosshatch pattern sent through the RF input does not

shut
the TV down. A color bar pattern sent to the video input does not shut the

TV
down. There is an X-Ray check toggle switch which I thought had been moved

to
the "check" position but trying it in the other position makes no

difference.
(Sometimes these plastic toggle switches have three positions even though

there
are only two selections.)

Thanks for everyone's suggestions so far. I'll keep plugging away at this.

Regards,
David Farber


Subject: Mitsubishi CS-2655R vertical jitter.
From: "Bill Jr"
Date: 04/30/2004 3:21 PM Pacific Daylight Time
Message-id:

Don't forget to get all the yellow/brown glue off everything.

Good Luck,
Bill Jr


"Chuck" wrote in message
.. .
On 29 Apr 2004 17:48:41 GMT,
(David Farber) wrote:

This Mitsubishi CS-2655R tv came into the shop with a blurry picture

and
not
much else wrong. I touched up the focus control and the picture is

crystal
clear except for some slight vertical jitter. I replaced all the C400

series
electrolytic caps and the vertical output IC, AN5521. The jitter is

apparent
whether you are watching a tv program or viewing the on screen display

menus. A
Google search for this fault didn't turn up much.

Thanks for your reply.


David Farber
David Farber's Service Center
L.A., CA


You need to clean the main circuit board, top and bottom, particularly
the video section after replacing the faulty capacitors. I have had
board leakage cause vertical jitter multiple times. Chuck




David Farber
David Farber's Service Center
L.A., CA