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First - Thank you Leonard, I have learned a ton by reading your troubleshooting posts in this forum. My problem is described below, if anyone has any additional suggestions.

Hi, I have a Mistubishi WS-65819 that I believe has a convergence issue. Diagnostic test gave "no fault" code, but I would get no picture. Occasionally I could get the TV to show a deep hourglassed, non color converged image for a few minutes by unplugging the TV for several hours and messing around with the pip input.

Searching the web showed recommendations for similar problems with other mitubishi RP TV's, but none for my model. This set doesn't have a DM, so the 4 cap replacement for the DM blink of death doesn't appear to apply. I looked at all of the caps on all of the internal boards anyway, though, and none show signs of doming.

I went ahead and ordered 2 new convergence IC's, STK 392-570, even though many people have had good luck by just resoldering the existing IC's. I don't know that a bad IC would certainly blow a fuse, so I am just assuming they are bad and replacing them. I'd only like to get into this set one time, if possible, so I'll be researching the cleaning/reconditioning tips on this forum also, after the repair is complete.

Opening the back of the set, I found some evidence of a CRT fluid leak, right over the board in the area where the CRT signals leave the board. I'm wondering if there are other components that I can check while I have the boards out that often fail with a CRT fluid leak, as I'd hate to button everything back up and find that replacing the IC's wasn't the solution. Tips on the proper fluids/techniques for cleaning this would be appreciated too, I've been using Isopropyl and q-tips to this point.

I've ohmed out all of the pico fuses I can see on the convergence IC board, but this leak was on the signal boad next to it. another thing I noticed was green-ish evidence of corrosion in the connector leaving the convergence IC board labeled "KA." This is the only spot I saw it, though, and those wires were bundled and colocated with other wires in the same area. I'm not sure if this is related to the CRT fluid leak or is unrelated.

Anyone have further troubleshooting suggestions or a service manual for this model to share?

Thanks,
Rob
 

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Discussion Starter #4
thanks, Leonard. I'm not sure the stuff I saw on the board was the CRT fluid, and the area affected was about the size of a dime. the stuff on the board was a light brownish color, and slightly gooey, but was located underneath the blue crt.

I haven't seen any signs of corrosion on that part of the board yet, but will continue to inspect. the corrosion I did see was inside a connector on the board with the convergence IC's were, but no signs of any corrosion or signs of fluid outside that connector shell.
 

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Discussion Starter #5
update:

after cleaning the board as you recommended, I'm now getting ~2 min of badly converged menu with no video display, and the set shuts down with a vertical deflection 2-4.

Can you help me determine which IC is the Vertical Output IC?

I'm referring to a previous post of yours:

Convergence problems usually will not cause the pix to go out unless a shorted chip takes out one of the supply line fuses. Then it won't come back. More likely is a bad solder connection on the vertical output IC or at one of the yoke connectors. Trace the deflection yoke connections back to find a small IC on a heat sink, usually with a location number in the 400s. Resolder the connections at the yokes and at that chip.
 

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If you are getting an image at all, you don't have a failed vertical output. More likely you are losing the signal to that IC due to a corroded connection, or loading the power supply down enough to cause shutdown somewhere else, like the convergence amps.

Time to get out your scope.
 
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