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Crumbtrail TV Forums: TV Equipment: TV Repair Forum:
Mitsubishi VS-5051

 

 


BLF62
New User


Oct 16, 2009, 3:30 AM

Post #1 of 5 (2055 views)
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Mitsubishi VS-5051 Can't Post

Hello,
Well I guess I need help since I came to this TV forum. Here's my story;
This last couple of weeks I had noticed the old VS-5051 just finally seemed dim and lacking color detail. In the past I have removed the back and cleaned the 3 CRT lenses and the mirror / screen. This time I went further and removed the CRT lenses as I had noticed a bug down in one. I never knew before those could be removed and cleaned. So I carefully took each lens off and cleaned all surfaces.
This made a huge difference getting rid of 15 years of dust, scummy film, and a few bug leftovers.
I bought a service manual online and went through the convergence and other settings just to try for the best picture.
Today I removed the covers again and cleaned the circuit boards from the dust build up. I carefully removed the main connectors and cleaned them.
I covered the crts to dial in electronic focus and convergence. After many hours adjusting I was satisfied that this was the best picture I was going to get.
I rolled the TV back into the living room.
Did one final convergence check making only some very slight adjustments. (Let me say I have read not to push these setting to hard and I did always stay under 200 on any one data value.
Anyway this was the best the TV had ever looked. I sat down and watched Comcast channels via the RF cable for a solid hour. I was actually kind of proud to have improved this old lady so much, not HD but damn nice.
Then disaster. All I did was switch the input to S-Video and call my girl to tell her how well the set was looking. (Sorry this is so long, but I wanted any body that might suggest help to have the history.) While talking to my girlfriend and having switched to S-Video input the set went way off on convergence. I say way off but not vertically. Horizontially the RED has tilted some 20 degrees CW and the BLUE is just the opposite. ANy suggestions would be most appreciated. Did I burn some driver transistor on the PCC convergence board? This just makes no sense to me as the set was looking so good and the only change was switching the input. The TV had been on and off many times since cleaning and on for several hours when this happened.
I have some pics if that helps.


(This post was edited by BLF62 on Oct 16, 2009, 3:11 PM)



BLF62
New User


Oct 16, 2009, 6:48 PM

Post #2 of 5 (2044 views)
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Re: [BLF62] Mitsubishi VS-5051 [In reply to] Can't Post

So no one with advice??
I did some more searching here and see that the convergence is a common issue and that my condition is sometimes called the "Bow Tie" symptom. It does resemble a bow tie effect.

I pulled the main pcb that contains the signal and convergence sections.
I found C8E02 was funky spilling its guts on the PCC board.
Found another bad cap on the AV board. C7A20 & C209
The STK391-020 ICs do not look bad and the solder joints also look good.
Could just that one cap on the PCC convergence board be the trouble.
Should I replace the STKs while I have it all apart?
Anyone?


Paulpablo
Enthusiast

Oct 17, 2009, 1:12 AM

Post #3 of 5 (2039 views)
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Re: [BLF62] Mitsubishi VS-5051 [In reply to] Can't Post

If it was in my shop, they would be replaced to prevent re-do in near future!


BLF62
New User


Oct 17, 2009, 3:49 PM

Post #4 of 5 (2034 views)
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Re: [Paulpablo] Mitsubishi VS-5051 [In reply to] Can't Post

Paul,
I also found a small resistor or pico fuse that looks bad.
It is R8D15 looks like some part of the power supply to that IC.
What are the best items to replace while I am in there?
I am trying to find the value of that pico fuse if that is what it is. Looks like a pale resistor and the colors do not match the resistance value on both it and its counterpart on the identical second IC.


Paulpablo
Enthusiast

Oct 17, 2009, 8:44 PM

Post #5 of 5 (2029 views)
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Re: [BLF62] Mitsubishi VS-5051 [In reply to] Can't Post

Sorry, I can't help you as I don't have a schematic for that set.

 
 
 


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