Viewsonic GF775 - unstable/reduced horizontal width only on the left side of the monitor.

[Franz Maurer]

Hi Folks,
My 4 year old Viewsonic GF775 (all LG parts inside) is starting to give me
trouble.
The left side of the screen gets reduced, the effect lasts for a while and
then it comes back to normal width, it only happens on the left side of
the screen. Can someone please advise?

Best regards,
FM --> Please post reply to the newsgroup or e-mail to
[email protected]

 

[Jerry G.]

Check for high ESR capacitors in the horiz scan circuits to start with.
These may be tricky to locate, because it sounds like your problem is
temperature sensitive. But, it is fixable.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
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Hi Folks,
My 4 year old Viewsonic GF775 (all LG parts inside) is starting to give
me
trouble.
The left side of the screen gets reduced, the effect lasts for a while
and
then it comes back to normal width, it only happens on the left side of
the screen. Can someone please advise?

Best regards,
FM --> Please post reply to the newsgroup or e-mail to
[email protected]

 

[Cher]

Something is changing the impedance of the deflection circuit.

Caps are definitely the first thing to look for.
Then look carefully at the yoke, especially if the humidity has been
high.

 

[Franz Maurer]

Hi Folks,
My 4 year old Viewsonic GF775 (all LG parts inside) is starting to give me
trouble.
The left side of the screen gets reduced, the effect lasts for a while and
then it comes back to normal width, it only happens on the left side of
the screen. Can someone please advise?

Best regards,
FM --> Please post reply to the newsgroup or e-mail to
[email protected]

I did not get to measuring ESR of the caps in the horizontal circuit;
still waiting for a promissed meter.
Yoke looks O.K.
There is another factor to horizontally shrinking screen. When I give the
monitor a light tap on the case it comes back to normal width. What do
you folks think about it? A sign of dying flyback? Or just a bad solder
joint somewhere in the horizontal circuit?

Regards,
FM

 

[Sam Goldwasser]

I did not get to measuring ESR of the caps in the horizontal circuit;
still waiting for a promissed meter.
Yoke looks O.K.
There is another factor to horizontally shrinking screen. When I give the
monitor a light tap on the case it comes back to normal width. What do
you folks think about it? A sign of dying flyback? Or just a bad solder
joint somewhere in the horizontal circuit?

Bad solder joint.

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