Thought we had this one licked but it failed.

Clean the living crap out of it, pour solvent all over the board and
it failed. This is the signal board, I found the leak. The red focus
was off so at the estimate stage I said "CRT socket". Wouldn't be the
first time, but in this case so much coolant had leaked the chamber
was only half full. The optical focus was off due to that.

There was actually a convergence problem masked by this condition. I
found it anyway, changed the O ring and cover plate of the CRT and
refilled it, making sure the bellows was collapsed.

Another symptom was the volume going up despite it's setting, I saw
the corrosion on the board and it was pretty much time to clean it. It
failed the next day and has again darkened my bench.

It had intermittent H drive, the six flashes of the standby light
means HSTOP, and as I got the print out and figured out where to hang
the scope probe, it started working.

Well I decided to clean the board more and actually found somemore
coolant under it, but not where I would expect. It was at the back of
the chassis. The way I figure it is that there is so much coolant
soaked into this board we could never get it all out.

When it fired up finally it had no color. Now, I have soaked this
thing pretty good with acetone, and at this point I am wondering about
the integrity of the cases of electronic components.

What I am wondering is if between the coolant and acetone there could
be damage either to the color as well as the 503K crystal, or if I
should change the jungle IC. Once the IC is out of there of course I
intend to give the PCB another cleaning.

But now there is another twist. The second time I cleaned it I
resoldered it, not that the connections were bad, but I was figuring
that this being a multiple layer board the coolant might be soaked
into it. I figured the heat would make it boil out.

Now it has stopped responding to the remote. That is a small issue
other than what I got when it comes to sweep and chroma. There is only
so much it can be.

There is a possibility I need a better technique to deal with coolant
on PCBs, what do you all do ? I do have a fairly decent success rate,
but I think this one is really soaked.

I am pretty sure this has been mentioned before, but it might be time
for another round, because anybody in the bigscreen business has more
experience with it, I can almost be sure.

Thanks for whatever you got.

JURB