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Jason F
 
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Thanks for the reply, but perhaps I didn't articulate--I could not find a
component that would respond to the freeze spray, at least in the way that I
was expecting (total failure of the pincushion correction like when the
monitor starts from cold).

I did discover something this morning. If you refer to the schematics:

"Jerry G." wrote in message
...
The freeze spray hit a component that has become thermo sensitive, if
something changed with the action of the spray going on it. Locate and
change that component, and you will have that fault fixed. You may find a
number of components that have become thermo sensitive with age.

--

Jerry G.
==========================


"Jason F" wrote in message
...
I've been hunting down several problems with a Sharp Image 429-DS-SY

monitor
(Dual-scan 15k/25k monitor with Sony Trinitron tube used in video games,

mfg
1998). I've totally recapped (the lytics) and replaced a diode in the

power
supply that had opened up. I'm so close to wrapping it up, yet keep

running
up against a wall with the last few issues.

Schematic: http://www.sharpimage.net/images/schematicD.pdf

In my latest saga, I've got a compressed right edge of the picture. From
everything that I know, this indicates that there's not enough current. I
would guess that perhaps it's a snubber cap issue, but I'm at a loss

looking
at the schematic which caps to suspect (I don't have values onhand to
substitute each one). Further confusing to me is the E/W correction
components (most of the stuff I work on are much simpler devices).

Next, there's a twitching of the image. Maybe 1 or 2 twitches (horizontal
size appears to increase for a fraction of a second) every couple of
seconds, sometimes a longer interval of a steady image. For this, I would
suspect cold solder, but I've touched up just about every solder joint and
still haven't found it. Could this be a component issue?

And finally, sometimes on cold start, the pincushion is really bad--as if
it's non-existant, and there's a really bad hourglass effect (looking at a
convergence grid pattern). Pulling out the freeze spray doesn't allow me

to
locate the fault once the monitor warms up and the pattern returns to
normal. Again, I'm suspecting cold solder could be the culprit.

Any tips or pointers for identifying cold solder joints? I've tried

tapping
and using a toothbrush, but no luck.