Looking for a schematic for this receiver. If anyone has one available I would appreciate E copy. Don't want to open it without a forehand look at the possible area to check. The fault looks either video or focus with one colour missing. Have schematics for kpr48 but not for 41". Check the normal sites for schematics but none. Thanks in advance for any help.
No e-schematic available, way too old. Probably 10 years pre-electronics service manuals at least.
Start with the basics. Given the age you could very well be simply looking at severely contaminated crt coolant. The blue could be almost totally blocked, the green mostly blocked.
Loss of one color should be pretty easy to track down without a schematic for 99% of the usual stuff.
The poor focus could very well simply be worn out picture tubes due to age, or convergence circuit failures.
If you need a schematic, you possibly cannot even buy one due to the age of the set. But worth a shot to try and borrow one on paper from a real service center near you.
Old ? 1986 !.
I have one but it might take some time to find it.
Point is you probably don't need it, what you described is probably coolant contamination. That set uses SD186 series tubes and to do a coolant change is very difficult. The upside is the the cooling system actually worked and you'll find very little phosphor burn-in, and the emission is likely to still be good. I've only seen one weak SD186 and it was a blue. I'm pretty sure someone had set the blue focus to dead sharp and cranked the drive. (you must leave the blue a bit out of focus on some PTVs, and this is definitely one of them)
If you determine it's coolant and decide to undertake the job, post back, there are a few caveats to know. Almost no TV shop will do it because it is so time comsuming.
JURB
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