Anybody have one, or know where to download one?
Have problem with picture rotating from top to bottom.
-Jan Finland
- posted
14 years ago
Viewsonic VP201b service manual??
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- Vote on answer
- posted
14 years ago
Finding service manuals / schematics for LCD monitors is pretty difficult.
I have several of these monitors (including the one I'm using as I type) and got to know it's layout quite well. I'm a little puzzeled by your description of the problem. Could you explain in more detail?
One place I repeatedly suggest people with monitor problems visit is
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It's a great place to get help.
PlainBill
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- posted
14 years ago
I will have to see, when I get it in front of me, but I was told that the picture rolls from top to bottom.
Anyway, I will get it in a couple of days, so I can give better description.
-Jan Finland
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- posted
14 years ago
I finally received this monitor and when I plugged it in, it worked perfectly. I decided to open it anyway, since I have been reading a lot about bad caps in Viewsonic's. I found that the main 400VDC filter cap was totally off from PCB on the + side and one dry joint on one of the power transistors. So, after few days of burn-in, it seems to fine. Thanks for pointing me right direction.
-Jan
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- posted
14 years ago
The original problem has come back, I guess the faults that I fixed, were not the correct ones. Here is a video of the fault, which seems to come and go:
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-Jan
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- posted
14 years ago
I would look for other bad caps in the power supply. Even the one you mentioned could be open-circuit. I often see caps in the 1000 to 2200 uF range bad, often with vented (bulged) tops, and more and more seeing the input filters (ex 150uF at 250 volt) snap-in types bad. Cheap crap...
Mark Z.
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- posted
14 years ago
I ESR'd all the caps on power supply PCB and they tested out fine. Also, no leaks or bulges.
-Jan
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- posted
14 years ago
A shame you didn't say so previously...
mz
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- posted
14 years ago
Are any of the caps in parallel? If so, one or more could be open, yet you still read a decent ESR from the good ones.
-- You can\'t have a sense of humor, if you have no sense!
- Vote on answer
- posted
14 years ago
Well, sorry about that.
Also the fault seems to have something to do with contact, since giving the display a slap on the top left corner (while the display goes crazy) makes it return to normal...
-J-
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- posted
14 years ago
Try re-seating the connectors in the sensitive part of the panel.
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- Vote on answer
- posted
14 years ago
I'd still watch out for that main filter cap; I've seen them be intermittent... and given that you saw a problem there I'd certainly keep it in mind.
Mark Z.