Viewsonic VA1912wb Recap

[junkmansam]

Well, I finally got to this project and complete recapping proved to make no improvement to the green 4 secs amber shut off problem.

Has anybody actually fixed one of these? I found a year old thread about this particular monitor and the OP never confirmed that he indeed fixed it.

Any thoughts?

[PlainBill]

Re: Viewsonic VA1912wb Recap

Well, I finally got to this project and complete recapping proved to make no improvement to the green 4 secs amber shut off problem.

Has anybody actually fixed one of these? I found a year old thread about this particular monitor and the OP never confirmed that he indeed fixed it.

Any thoughts?

Do you still have the white bars floating up the screen? Have you tried it hooked to a computer?

PlainBill

[junkmansam]

Re: Viewsonic VA1912wb Recap

Hi Bill, No white bars just black with that dialog box. Is that a good thing that they are gone?

I check all pins and they are straight.

I haven't tried to hook it up yet. I'm gonna double check my solder work and see if everything is ok. Maybe within the next hour or so I'll post the results.

Thanks

[PlainBill]

Re: Viewsonic VA1912wb Recap

Hi Bill, No white bars just black with that dialog box. Is that a good thing that they are gone?

I check all pins and they are straight.

I haven't tried to hook it up yet. I'm gonna double check my solder work and see if everything is ok. Maybe within the next hour or so I'll post the results.

Thanks

That is a very good thing. The white bars were caused by noise on the power supply lines. Normally after a period of time without a video signal the screen. Four seconds seems very quick, but we'll know more if you hook it to a computer.

PlainBill

[junkmansam]

Re: Viewsonic VA1912wb Recap

Ooops, forgot a small cap 22uf 50v. Do you think it should be replaced being so small? I don't have any 22uf's in my stash so I'll have to go to RS.

I don't understand the purpose of hooking it up to a computer at this point. Could you elaborate please?

[PlainBill]

Re: Viewsonic VA1912wb Recap

Ooops, forgot a small cap 22uf 50v. Do you think it should be replaced being so small? I don't have any 22uf's in my stash so I'll have to go to RS.

I don't understand the purpose of hooking it up to a computer at this point. Could you elaborate please?

I wouldn't worry too much about that cap. If it were bad the power supply wouldn't start up.

In general, all LCD monitors work in the same way. When power is applied the controller checks the status, and if it lost power while 'off' (black power LED) it will return to that state. If it was 'on' (green or amber power LED) it will turn on the backlights and check for a video signal and display it if a signal is present. If no signal is present it pops up a 'no signal' message, then after some time period will turn off the backlight and switch the power led from green to amber.

As with many things, the specific details differ with each brand of monitor. Some Dells check if they are connected to a computer. If so, they go to sleep within 10 seconds of no signal. If not, they display a marching test pattern for minutes. Other brands will simply go to sleep within 10 seconds. Some will respond to front panel menu button even if no signal is present. Others won't. Right now that monitor is acting like a working monitor with a very short shut down period.

PlainBill

[PCBONEZ]

Re: Viewsonic VA1912wb Recap

In other words you -may- need it connected to a PC so it doesn't turn off the back lights while you are trouble shooting.
.

[PlainBill]

Re: Viewsonic VA1912wb Recap

In other words you -may- need it connected to a PC so it doesn't turn off the back lights while you are trouble shooting.
.

Or there MAY be nothing to troubleshoot.

PlainBill

[junkmansam]

Re: Viewsonic VA1912wb Recap

Thanks I'll hook it up possibly tomorrow cause I need to get a cable. I'll keep you posted. Later

[junkmansam]

Re: Viewsonic VA1912wb Recap

Or there MAY be nothing to troubleshoot.

PlainBill

Well Bill, you were correct in your assumption. Thanks a lot. Here is a pic of her all lit up.

One other minor problem. One of the bigger value caps is taller than the original and the top comes in contact with the metal cover. I was thinking of putting a piece of electrical tape between the cap top and the metal cover. Is that neccessary?

[PlainBill]

Re: Viewsonic VA1912wb Recap

Well Bill, you were correct in your assumption. Thanks a lot. Here is a pic of her all lit up.

One other minor problem. One of the bigger value caps is taller than the original and the top comes in contact with the metal cover. I was thinking of putting a piece of electrical tape between the cap top and the metal cover. Is that neccessary?

Necessary? Probably not. But a very good idea. Or glue on a piece of fish paper.

PlainBill

[PCBONEZ]

Re: Viewsonic VA1912wb Recap

Fish paper?
Wassat?

When that comes up I'll usually either stick some electric tape on the inside of the cover or if it's a hot spot I'll cut a clearance hole in it for the cap.
You can also lay the cover on a piece of soft wood [like white pine] and rap it with a hammer to make a clearance dimple in the sheet metal.

[PlainBill]

Re: Viewsonic VA1912wb Recap

Fish paper?
Wassat?

When that comes up I'll usually either stick some electric tape on the inside of the cover or if it's a hot spot I'll cut a clearance hole in it for the cap.
You can also lay the cover on a piece of soft wood [like white pine] and rap it with a hammer to make a clearance dimple in the sheet metal.

Google it.

PlainBill