Riddled TV Repair Forum

dougq · Joined: 29 May 2012 Posts: 3 Location: Canada

Hi: The approx. 15% of the bottom of the screen is compressed to a single line leaving a dark screen over that 15%.
The top has also about 15% expanded and rolled over the top.
I suspect an electrolytic in the vertical, but just a guess. Smile

Any help appreciated.

Thanks

DougQ

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JTS1957 · Joined: 21 Jan 2009 Posts: 2395 Location: Far, Far Away

Start at the vertical output device and replace each electrolytic, spiraling outward (clockwise or counter-clockwise, makes little difference, whichever you prefer) until you resolve the defect or run out of real estate. Wink

dougq · Joined: 29 May 2012 Posts: 3 Location: Canada

Thanks for the reply.
I found this comment on locating the vertical section.
Is it accurate?
"To locate the vertical section, follow the four wires going from deflection yoke, ie, coil fitted on the neck of the picture tube. There will be four of them, out of which two of them will be thin relative to the other two. Usually color coded as blue and yellow. Colour code should always not be the same as described, and it can be changed to set by set. Any way these four wires reach to the main board and socket-ed there. Follow the track on the print side of the board, where the above said two thin wires are connected, and you will reach to the vertical output section. "

I have found the plug mentioned, so at least now I have a starting point.

Thanks.

Doug

JTS1957 · Joined: 21 Jan 2009 Posts: 2395 Location: Far, Far Away

You could always try looking on each heat sink for a device with a number LIKE: LA78xx.

dougq · Joined: 29 May 2012 Posts: 3 Location: Canada

Hi: I have not done anything as the set has started working normally?
Does that indicate a cold solder joint, or can a cap be intermittent in that way??

Thanks again.

Dougq

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