On Fri, 27 Aug 2004 02:59:49 GMT, Ross Herbert
wrote:

On Thu, 26 Aug 2004 06:11:19 GMT, "Jim Beaver"
wrote:

|I've got a bulky Sony Trinitron XBR exhibiting weird symptoms. First I
|noticed that it was taking an inordinately longer time to come on when
|turned on. It takes anywhere from thirty seconds to two minutes to get the
|degaussing click and for the red light to start flashing on the front of the
|cabinet. Once those two things happen, it warms up and pictures up within
|the normal time frame.
|
|Then, after a few days of this, it began turning itself off and eventually
|back on, usually at but not restricted to times when my air conditioning
|system cycled on. There is a dark transluscent strip at the top front of
|the cabinet, above the screen, that lights up a dim red after the set has
|turned itself off. This dim red glow continues for however long it takes
|the set to get back to being ready to come on again. Then the red glow goes
|out, the set clicks, the red light starts flashing, then the set comes back
|on as though nothing had happened. Ten minutes or five minutes or half an
|hour later, it does it again. Like I say, it's usually when the air
|conditioner comes on, but not always.
|
|A minor and unrelated problem: I can't find my remote for this set, and
|can't figure out how to get rid of the word 'LINE' displayed on the screen
|in the lower right. It's been there for weeks. I know there's probably a
|menu or display button on the remote, but how can I get rid of it without
|the remote?
|
|Sorry I haven't got exact model numbers. It's a huge set, too big for me to
|manhandle by myself, and it's in place in a TV armoire and I can't readily
|access the back.
|
|Thanks.
|
|Jim Beaver

To me this sounds like classic SMPS pulse by pulse current limiting
due to drying out of electrolytic caps in the power supply. That would
be the first place I would start checking.

Ross H
Hi Ross, I did a visual inspection of the power supply board,
and I couldn't see any signs of degredation. Would the "drying out"
be visible?

On the main circuit board (The A board) I did see a
transformer, a one inch square block that was covered in
a white, powdery-looking substance which didn't clean
off easily. Eventually I was able to get most of it
off using an electronics spray. That was the only component on the
whole board that actually looked sick. This part is known as
T503 HDT in the service manual. Ant relevance?
Thanks,
Dave