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Old 12-28-2017, 03:46 PM   #41
budm
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

I am glad you got it figure out, some how it got corrupted.
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Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
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Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

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http://www.badcaps.net/forum/showthread.php?t=24809
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Old 12-29-2017, 02:04 PM   #42
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Yay, another monitor saved! Good job, rddube! This repair is all on you and don't let anyone tell you otherwise.

Indeed there must have been some corruption going on as budm suggested - perhaps the bad caps caused the monitor to corrupt the factory settings saved in BIOS. I think I do recall seeing a thread in badcaps.net here a very long time ago where someone had a similar issue after a recap.

Regarding the menu options, I think ADC OFFSET is to set the correct for any offset in the midpoint of all the colors (RGB). Meanwhile, ADC GAIN is likely something to do with the contrast / color curves / gamma. I'm not 100% sure to be honest, but it does look a bit similar to some of the colors settings I've fiddled with on my high-end CRT monitors. The rest should be self-explanatory, more or less. The "9300K", "7500K", and other numbers are probably factory-preset color temperatures (with the "9300K being the most "blue" and the "5400K" the most yellow/red, or sepia-like). As for the settings on the second page - I'm not quite sure about those.

Anyways, congrats on the repair again and cheers!

Last edited by momaka; 12-29-2017 at 02:06 PM..
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Old 12-30-2017, 06:49 AM   #43
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Was the monitor also flickering before you adjusted the Vcom value?
Read here for some details on what it adjusts:
https://www.intersil.com/content/dam...n12/an1208.pdf
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Old 12-31-2017, 04:48 AM   #44
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

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Originally Posted by Per Hansson View Post
Was the monitor also flickering before you adjusted the Vcom value?
Read here for some details on what it adjusts:
https://www.intersil.com/content/dam...n12/an1208.pdf
Hello Per Hanson,

How interesting - actually, the monitor was not flickering before I adjusted Vcom value, but since adjusting (the value goes from 0 to 255) I have found that the optimal value is 122, not 128 for image quality.

But, I did notice that when it comes out of sleep mode, it does flicker for approx. 30 seconds right in the middle of the screen (about 2" X 4") and stabilizes after that or it will also stabilize if I display a page with white in the middle of the screen (pure white). Not sure what is causing this, but it wasn't doing that before the recap and corruption.

I'm not sure I understood all the parts of the article you sent, but I think it might be related. The interesting thing is that when I initialize the EEprom in the menu, the Vcom value doesn't change. I also tried auto color and auto config but it doesn't change anything.

Additionnally, when I have that flicker from waking up, I also have a vertical band as you can see in the picture attached that also disappears within the same time frame as the flicker.

Not sure what I should try, but if you have any ideas, I am prepared to test and post.

Thanks again for your intervention!
Attached Images
File Type: jpg P1000424.jpg (448.8 KB, 9 views)
File Type: jpg P1000425.jpg (728.2 KB, 6 views)
File Type: jpg P1000426.jpg (873.2 KB, 6 views)
File Type: jpg P1000427.jpg (922.5 KB, 3 views)

Last edited by rddube; 12-31-2017 at 04:50 AM..
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Old 01-01-2018, 08:34 AM   #45
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Ok fixed the flickering problem by adjusting another setting on page 2 of the factory menu called digital bri. which probably means digital brightness. It was at 128 and by lowering down to 102, this fixed the flickering in the middle of the screen when coming out of sleep mode, without much impact on image quality.

Hope this might help someone else with same issue.
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Old 01-01-2018, 01:37 PM   #46
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Nope, still doing that flickering in the middle of the screen (approx 2" X 4") when monitor comes back on - for about 30 seconds, as if something needed to heat up before it stops. Any ideas anyone?
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Old 01-06-2018, 10:26 AM   #47
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

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Originally Posted by rddube View Post
Nope, still doing that flickering in the middle of the screen (approx 2" X 4") when monitor comes back on - for about 30 seconds, as if something needed to heat up before it stops. Any ideas anyone?
Hmmm. Maybe the CCFL tubes are getting a bit old at this point? Do you know how many hours the monitor has been running for so far (there may be an option in the service menu to tell you that). From what I've seen, it's mostly old monitors with lots of use that start to flicker. But it could be something else too. To be honest, I'm not too sure at this point. Hopefully we can get more input from other members.
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Old 01-07-2018, 05:12 AM   #48
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Hey Momaka,

Well it is an older monitor (2005), so that may be it. I wasn't able to find any data in the service menu that would indicate number of hours powered on.

Well I guess I'll just have to live with it unless someone else has any ideas? Tks!
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Old 01-07-2018, 11:16 AM   #49
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

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Originally Posted by rddube View Post
Hey Momaka,

Well it is an older monitor (2005), so that may be it. I wasn't able to find any data in the service menu that would indicate number of hours powered on.

Well I guess I'll just have to live with it unless someone else has any ideas? Tks!
I have one of these at work, I think I recapped it around 2011 or 2012, still going strong on a colleagues desk.
Do you want to know its values?
From your description it sounds like you press up, down, 1 and 2 all at the same time for factory mode??
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Old 01-08-2018, 10:57 AM   #50
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Hi Sean,

Yes if you could take a photo of page 1 and page 2 of the factory menu that would certainly help. To get to the factory menu, the monitor has to be hooked up to a DVI or VGA signal. Then you press "power key" to turn off the monitor. While it is off, you press" [▼] +[▲] + "power Key" "at the same time so as to enter factory mode. After power on, press ''Menu[1]'' key, you can see the Factory menu.
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Old 01-12-2018, 03:48 AM   #51
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Default Re: Viewsonic vx2235wm colors washed out after power board recapping

Quote:
Originally Posted by seanc View Post
I have one of these at work, I think I recapped it around 2011 or 2012, still going strong on a colleagues desk.
Do you want to know its values?
From your description it sounds like you press up, down, 1 and 2 all at the same time for factory mode??
Hi again, any chance you could get those photos of the factory menu?

Many thanks!
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