working on a viewsonic lcd model va720 with a strange problem; it starts out fine has a great picture for aprox 1 hour then half the screen right side gets distorted & whitish
it is from top to botom & takes up half the screen.If you turn the monitor off then on again,picture will be good again for 5 seconds then distorts again.I have tried to freeze components but no luck. please help if you can.
thanks.....tbmanitou

You did not have to post this question 2 times.

Obviously there is a component that is temperature sensitive. When the
monitor is heating up, the component starts to go off value.

You can usually find these with a heat gun, and a can of freeze-spray. You
can heat and cool the various areas until you zero in on the faulty
component(s). Most of the time capacitors cause this type of fault in these
monitors.

The components in your monitor are mostly surface mount types. You will have
to have the parts source and the proper tools, and be prepared to do surface
mount type soldering to change most any of the defective parts you find.

Normally Viewsonic, as like the rest of these manufactures, hardly service
these boards at the component level. They change the complete circuit board,
and then use their interface system to do the setup of the new board if
necessary. As for parts and service information, they do no sell this to non
authorized contractors for them. Unless you are very innovated, in the end
you will probably have to send them the monitor for service.

--

JANA
_____


"tbmanitou" wrote in message
...

working on a viewsonic lcd model va720 with a strange problem; it starts
out fine has a great picture for aprox 1 hour then half the screen right
side gets distorted & whitish
it is from top to botom & takes up half the screen.If you turn the
monitor off then on again,picture will be good again for 5 seconds then
distorts again.I have tried to freeze components but no luck. please
help if you can.
thanks.....tbmanitou


--
tbmanitou

"JANA" wrote in message
...
You did not have to post this question 2 times.

Obviously there is a component that is temperature sensitive. When the
monitor is heating up, the component starts to go off value.

You can usually find these with a heat gun, and a can of freeze-spray. You
can heat and cool the various areas until you zero in on the faulty
component(s). Most of the time capacitors cause this type of fault in
these
monitors.

The components in your monitor are mostly surface mount types. You will
have
to have the parts source and the proper tools, and be prepared to do
surface
mount type soldering to change most any of the defective parts you find.

Normally Viewsonic, as like the rest of these manufactures, hardly service
these boards at the component level. They change the complete circuit
board,
and then use their interface system to do the setup of the new board if
necessary. As for parts and service information, they do no sell this to
non
authorized contractors for them. Unless you are very innovated, in the end
you will probably have to send them the monitor for service.

--


It was probably a glitch with his news reader, not a big deal.

Also he said he already tried freeze spray, I'm surprised that it didn't
locate the problem though as it does sound like a thermal issue.

thanks for your reply,I thought it was a heat related problem also that is why i freeze misted all components but to no avail! i still have not found any components that are breaking down thermaly,you are probably correct in sumising that the monitor has to be repaired by a factory authorised service centre but i thought that i would get lucky and repair this at component level since i don't believe in changing boards unless absoulutely necessary.