Re: VP201b Heat-Related Screen-Half Flake Out

You mentioned that you have another VP201?

If so try swapping the panel from that unit to this, or the pcb's from this "half display" unit to the spare display.

What I'm getting at is that this similar problem is with Dell 2001FP and it uses the same panel as this Viewsonic and I solved the problem by swapping the panel from a different display and now the Dell works fine because the problem was with the panel, not with the displays PCB's.

-Jan

Re: ViewSonic VP201b

That is a very good question. I was wondering that too. I know that "normal" electrolytics can be measured reliably while in ircuit, but I'm not sure about SMD's.

Well the second VP201b had a bad inverter (fuses and caps fine). Backlight flashed briefly at startup so I replaced the inverter and it seems to be fine now. Ihad a spare inverter from my first VP201 from which I borrowed the panel to fix a vertical striped Dell 2001FP (the vertical stripe is caused by defective panel).

-Jan

Re: ViewSonic VP201b

I got another VP201b to play around with. It had some problems when picture was very bright it starts to flicker.

I checked the power and inverter caps, they were file, then I started to check the main board SMD caps and some were 2-10 times the ESR what they are supposed to be.
Has anyone replaced these main board caps?

-Jan

Re: ViewSonic VP201b

If you back up a little bit on that FTP address, there are many other service manuals for other Viewsonics too:
[url]http://ftpkuban.com/FTP/Manual/ViewSonic/[/url]

-JanRe: ViewSonic VP201b<br /> <br /> ... <br /> -JanRe: ViewSonic VP201b

If you back up a little bit on that FTP address, there are many other service manuals for other Viewsonics too:

Re: ViewSonic VP201b

No, I did not measure the voltage and there is really no sound at all.
The picture starts doing that first slowly and the faster and finally it stops, like cut with a knife and picture returns to normal.
I checked all the caps on the power supply, but not the video/control PCB.

Actually, it does not seem to be backlight problem, since the backlight does not flicker at all, it just looks that way, since youtube downgraded the avi file so much.
The backlight stays at constant brightness all the time this is happening.
...

Re: ViewSonic VP201b

It seems that after a few days of working fine, the original fault has returned and it seems to come and go.
Here's some video of it in action:
[url]http://www.youtube.com/watch?v=azFRo8uhad0[/url]

After I filmed this, it returned to normal and has been working fine for a couple of hours now.

-JanRe: ViewSonic VP201b<br /> <br /> ...Ro8uhad0[/url]

Re: ViewSonic VP201b

Hello to everyone, since this is my first post on this forum!

I just received a malfunctioning VP201b and the original owner claimed that the picture rolled from top to bottom.
However, when I unpacked it, it functioned perfectly, hmm...
Since I have been reading a lot about the bad caps in Viewsonics, I decided to take a look inside.
It looked like someone had been there before me, but I removed the power supply to measure the ESR on caps. I found that they were fine, BUT the main 400v cap was totally broken off from is soldering...