Viewsonic VP211b

[Welchs101]

Re: Viewsonic VP211b

Well, i was able to solder the caps on the board but I could not fully remove the "power supply board". I had to turn it upside down as far as i could and solder this way.

[PlainBill]

Re: Viewsonic VP211b

Plain-Bill,

How did you disassemble this monitor. I need to remove / replace a few capacitors on the power supply board but i cant seem to get it out of the "steel frame".

Any thoughts?

DamnifIremember. All I remember at this point is it was a bear to get the back off the case. How about a picture showing what you are dealing with?

PlainBill

[Welchs101]

Re: Viewsonic VP211b

Plain-Bill,

How did you disassemble this monitor. I need to remove / replace a few capacitors on the power supply board but i cant seem to get it out of the "steel frame".

Any thoughts?

[EGuevarae]

Re: Viewsonic VP211b

This is the first LCD panel I disassembled, so I don't know how others do it. Samsung makes this panel. It uses 6 CCFLs, three at the top, three at the bottom. The CCFLs are arranged side by side inside a C shaped 'cartridge'. This is a piece of light steel that has been painted white for reflectivity. They are held in place by running the leads through silicon rubber fittings at each end of the cartridge, and several spacers along the length of the tubes. The leads from the 'hot' end of the tubes goes directly to the inverter. The leads from the 'cold' end of the tubes run along the back of the cartridge, then are bundled with the hot leads inside heat shrinkable tubing, where they connect to the inverter. By removing 4 screws on the front of the frame, carefully loosening the latches holding the plastic and metal frames together, then removing a very tiny screw which anchors the cartridge to the metal frame, it is possible to remove the cartridge as an assembly.

When I pulled the bottom cartridge from my monitor I discovered that the end of the cartridge was discolored under two of the tubes. On the back side of the cartridge the silicon wires were obviously overheated, and there was a 1/4" length of uninsulated wires that could contact the metal. When I replaced it with a cartridge from a monitor that had a few nicks in the covering the dark lines were greatly reduced. It's not perfect, but it works very good for a $12 monitor.

No, I am NOT going to take the monitor apart again so I can take pictures.

PlainBill

I used to have one working unit of this model (and have two non working) and the explanation is pretty good. And no, I won't open one panel either to take pics - fragile stuff. But I promise to take them the next time I tear apart a panel.

[PlainBill]

Re: Viewsonic VP211b

This is the first LCD panel I disassembled, so I don't know how others do it. Samsung makes this panel. It uses 6 CCFLs, three at the top, three at the bottom. The CCFLs are arranged side by side inside a C shaped 'cartridge'. This is a piece of light steel that has been painted white for reflectivity. They are held in place by running the leads through silicon rubber fittings at each end of the cartridge, and several spacers along the length of the tubes. The leads from the 'hot' end of the tubes goes directly to the inverter. The leads from the 'cold' end of the tubes run along the back of the cartridge, then are bundled with the hot leads inside heat shrinkable tubing, where they connect to the inverter. By removing 4 screws on the front of the frame, carefully loosening the latches holding the plastic and metal frames together, then removing a very tiny screw which anchors the cartridge to the metal frame, it is possible to remove the cartridge as an assembly.

When I pulled the bottom cartridge from my monitor I discovered that the end of the cartridge was discolored under two of the tubes. On the back side of the cartridge the silicon wires were obviously overheated, and there was a 1/4" length of uninsulated wires that could contact the metal. When I replaced it with a cartridge from a monitor that had a few nicks in the covering the dark lines were greatly reduced. It's not perfect, but it works very good for a $12 monitor.

No, I am NOT going to take the monitor apart again so I can take pictures.

PlainBill

[Bobdee]

Re: Viewsonic VP211b

It's not a 'line' problem, it was a "line" problem.

On dark green or dark gray backgrounds there were two darker wavy lines that varied between 1" and 1/2" high. The extended about half way across the screen before fading out.

This could not have been related to the horizontal or vertical drivers, the flex cables, or anything related to them. In fact, it was caused by a poorly assembled backlight 'cartridge'.

PlainBill

Hello Plainbill
Can you help me out please, I seem to be missing something here I have been into a number of b/light units to replace CCFLs or removing rainwater in some cases, I can understand the panel being the cause but not the units assembly
what exactly was the fault in there ???
Can you enlighten me please
Many thanks for a reply
bob

[Toasty]

Re: Viewsonic VP211b

>>In fact, it was caused by a poorly assembled backlight 'cartridge'.<<

Again - 'splain Lucy

[PlainBill]

Re: Viewsonic VP211b

No need for pictures, etc. I figured it out nearly a month ago. I'm using the monitor right now.

PlainBill

[mladen82]

Re: Viewsonic VP211b

[mladen82]

Re: Viewsonic VP211b

maybe this picture can help you


middle chassis is plastic frame, be aware that this is for lcd tv panels but with lcd monitors you only have two pair of ccfl, up and down

[mladen82]

Re: Viewsonic VP211b

This could not have been related to the horizontal or vertical drivers, the flex cables, or anything related to them. In fact, it was caused by a poorly assembled backlight 'cartridge'.

PlainBill

if problem is with backlight unit, you can disassemly carefuly, but be aware any dust will easily stay inside backlight films

The panel seems to be built on a stainless steel frame. Everything seems to be held in place with a white plastic back frame with four 'catches' on each side. These latch into slots in the front frame. There are four screws of unknown purpose on the front of the metal frame. Of course, there is also the cover over the electronics section of the display.

face down lcd on soft cloth, remove four crews, and the cover
then use flat screwdriver to unlatch catches
then turn over lcd and carefuly remove metal frame
lcd panel is probably sealed together with plastic frame, you can carefuly try on edges with flat screwdriver to pull, try to avoid touch panel with fingers inside but you must remove lcd from plastic frame
then you have only backlight assembly (diffuser thin plates and one thick), i have reassembled many but always was dust reamined inside them
i had only problems with bad ccfls
sorry for bad english, if i can help with some photos i can help tomorow at job...

[Toasty]

Re: Viewsonic VP211b

'splain Lucy

[PlainBill]

Re: Viewsonic VP211b

do you have some photos of that line problem?
lines are only repairable buy specific service centers like this one
http://elsin.cz/en/lcd-repair/defects

It's not a 'line' problem, it was a "line" problem.

On dark green or dark gray backgrounds there were two darker wavy lines that varied between 1" and 1/2" high. The extended about half way across the screen before fading out.

This could not have been related to the horizontal or vertical drivers, the flex cables, or anything related to them. In fact, it was caused by a poorly assembled backlight 'cartridge'.

PlainBill

[mladen82]

Re: Viewsonic VP211b

do you have some photos of that line problem?
lines are only repairable buy specific service centers like this one
http://elsin.cz/en/lcd-repair/defects

[bullwinkle]

Re: Viewsonic VP211b

be careful on flex cables. they are very sensitive since they carry the TAB. Carelessness will bring your LCD screen unuseable anymore

[PlainBill]

I picked up this oldie as a Freecycle freebie. Replacing an open fuse in the inverter fixed most of the problems, so I put it to work on my desk. Gradually I became aware that the display was not working properly. Specifically, on a dark green background two broad (about 1") lines ran 2/3rd of the way across the screen. It was not noticeable on a white background, but was barely visible on a blue background. The first cause that came to mind was the CCFL backlights (something had to blow that fuse, right?)

Opening up the case and isolating the LCD panel itself was easy, but now I'm into unfamiliar territory. The panel seems to be built on a stainless steel frame. Everything seems to be held in place with a white plastic back frame with four 'catches' on each side. These latch into slots in the front frame. There are four screws of unknown purpose on the front of the metal frame. Of course, there is also the cover over the electronics section of the display.

So how do I disassemble this without breaking something?

Thanks,

PlainBill