Screen has dark area in upper left, and shows double images in area next to that. Is this a color gun problem? Can it be fixed easily/

Try replacing the tcon board

Hello... Rear Projection TVs are not easy to work on. That being said, color issues can be caused by several different things. The most common involves the CRTs (there are three small picture tubes). There is a fluid in each tube that over time can dis-color, and involves a very difficult procedure to fix. Next, there are convergence circuits for each CRT, and one or more can fail. This will not usually cause the symptom you are describing, it will usually cause a double image in some or all areas of the screen and some areas the colors will look fine while other areas will not. It could also be a bad CRT drive board, or the video processing IC. It could even be the high voltage splitter! If I were you, I'd consider a new TV (please get the extended warranty). I hope this helps...

I answer questions for free.
I understand electrical devices.
It is unclear how many screws are on the switch you are testing.

If your switch does not show ohms when the switch is in one position, then it sounds like the switch is bad. But you can read information below for more information about your testing.
You can also add a comment and continue the discussion.

Let me provide more information about switches because you seem interested in electricity and the information may help us understand where the other is coming from in case you add a comment needing more help:
2 screws on switch: (excluding ground screw)
An ordinary single-pole switch usually has 2 brass colored screws.
These screws only read ohms or continuity when switch is in one position.
When the switch is in the other position, there are no ohms that pass through the switch.

3 screws on switch: (excluding ground)
A 3-way switch has 3 screws. There are 2 brass-colored screws and one dark-colored screw.
Put ohm tester on dark screw and continuity will show between the dark screw and one of the brass screws.
Flip the switch and ohms will test between dark colored screw and the other brass screw.

4 screws on switch. (excluding ground)
There are 2 screws on each side of switch.
This type of switch might be a special purpose double-pole switch.
Or it might be the more common 4-way switch.
Add a comment if you have a switch with 4 screws.

Below is a typical 3-way switch application showing the dark-colored screws:



Here is a typical 4-way switch circuit:
Notice the switch in middle has 4 screws:


Link below goes to a special application double-pole-double-throw switch:
http://waterheatertimer.org/images/30-Amp-DPDT-switch-a-800.jpg

This is for a Mita 1560 Photocopier (analog)
J50 was caused by exit sensor not sitting correctly in its bracket,I fixed this by pushing it until it
clicked back in.
The dark lines & double imaging can be caused light getting onto the drum ,or if the drum gets
cold (so I have been advised) which one it was for sure I will never know because when I
returned the next day & fixed the exit sensor the copy was OK.

The liquid coolant between the guns and the lenses may be fogged, low, or both. If the red gun has fogged coolant, you'll see red fringing around objects. It can be drained and refilled with new coolant, but it's gotta be the right stuff. You may be able to get some from a junk set, as I have done with success. Shine a light into the front of each lens. If the liquid has gone bad, you'll be able to see it.

You could have some type of convergance (three colors, three guns) problem. Also a misaligned horizontal or vertical oscillator.Ceck to see if any of tiny magnets around the bell of picture tube or next to coils in and around bell of pix tube are missing.

You need to use the convergence feature for your set. What this is is having the three color guns aligned properly, There is hopefully an automatic adjustment on your set-up menu, if not adjustments for each seperate gun. Basically you adjust the lines of the adjustment screen so the line turns black and white. You can easily see what needs it.

If this needs to be done manually, it is a chore. Contact me for directions how to do this. It is best left to a pro but this can get costly and wouldn't hurt if you tried yourself as if someone comes in, the cost would be the same whether it is out slightly or severely.

Jeff

I have the same problem and now there is convergence problem with the entire screen, double images and ghosting ...i was told that some IC's are burned our ...etc..i'm waiting to see if they sell the entire board since the TV's are 10 years old... will let U know what i get as a response.

not sure but you could have a bad color wheel i would suggest a service call from your local shop

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