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Mark Zacharias Mark Zacharias is offline
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Default Sony Kp51WS500 really stuck

"Leonard Caillouet" wrote in message
...
wrote in message
...
On Jun 8, 6:04 am, "Mark Zacharias"
wrote:
wrote in message

...
On Jun 6, 12:19 pm, varocketry wrote:





.


There is a bad picofuse on the power supply board. I previously
mentioned
this possibility in addition to the fuses under the heat sinks.


quote:


"There are some Sony models which get a bad picofuse on a separate
power
supply board when the convergence amps fail, in addition to the
picofuses
hiding under the STK's heat sinks"


Mark:


I agree from my reading of extensive discussion at the TECHLORE.com
site. Therer apparently are two (2) PICO Fuses on the G Board that
you haver to check also.


Several indepth articles and discussions on the OSNY convergence
problem, these STK you reference , etc. there. It's a plu, for sure,
but only because it's the best info site on these issues I've found.


I'm repairing my SONY KP-61XBR38 convergence issues now. My set uses
different boards and ICs so it's not as cookie cutter.


Also, the moderators from that site have their own REPAIR KIT website
(tvrepairkits.com) where they bundle all the typical parts, paste, and
INSTRUCTIONS into a kit for hobbyist use.


Hope this helps.
You were very clear Mark but I missed that part of your reply. I saw
the vertically mounted board on the left side. I never checked it
thinking that all pertinent fuses would be on the deflection board. I
remember thinking that there may be a fuse on that board. We'll give
it another shot next week. BTW, what is the trick to removing the HV
wires? Thanks, Lenny.


We have another guy in the field who brings me these boards. There is a
tool
he uses to get the high voltage leads out, but can use a drink straw in a
pinch. The straw is slit so as to go around the red wire, pushed down
into
the FBT so as to get between the flanged cap on the wire and the
surrounding
inner part of the FBT. Pretty tricky though - I hate that kind of thing.
On
the rare occasion that I work on the whole TV in the shop, as I recall, I
dismount the HV splitter which allows me more room to stretch the wires,
and
just do the soldering etc while sitting there on the floor.

I don't think you need to do this though. Just pull the power supply
board,
which does not include the FBT, and replace the picofuse(s).

Mark Z.- Hide quoted text -

- Show quoted text -


The old drink straw trick. I remember that kind of tool. We used
something like that to remove pins from Cannon connectors on the
flight computer chassis on the C141A. It was made out of tough teflon
as I recall. That was 40 years ago though so I don't remember
much.....I can try the straw. Thanks. What do you think about the
other part of my question though? Do you think I'm in trouble? Lenny..


You don't even need to remove the anode lead. I do these all the time.
Just rotate the board with everything disconnected except the anode and
focus leads. Just be gentle and don't pull on them.

You should not need a tool for these if you never yank on them before
trying to remove them properly. Just push the wire in, twist it about a
quarter turn, and it should come out easily. If you pull on it first, you
spread the clips and even the straw trick may not work.

What most people miss on these sets is that they almost always have
excessive d.c. offset of 200-400 mV on the inputs to the ICs from the DCU,
which results in about the same on the outputs. It is best to keep the
offset lower. My rule of thumb has always been less than 100mV.

Leonard




I forgot about the twist trick!

mz