Hey there everyone,
I recently aquired a SHARP 28JW-73H 16:9 100Hz CRT TV through the wonderful freeshare network of Glasgow, Scotland. When I got it back to my house following a fairly benign car journey the TV would occasionally show a green cast, other times showing a perfect picture. Cycling the power button would normally fix this. The problem got worse, for no obvious reason until the image was always green cast.
Anyway to cut a long story short, found the service for the Sharp GA-200 chassis, got into it's service mode to see if there was any 'return to factory defaults' or similar option, messed around (Uh oh!) with the options for {R,G,B} Gain & Cutoff to no avail, then read about degausing the screen with another CRT monitor. I was dubious as I'd heard the TV degausing a few times since the problem appeared. Tried it and it seemed to solve the green cast - now it was blue! ;-)
Went back into the Service mode and set Gain & cut off to similar values for both R,G & B. Cycled the power button and first thing I saw was strong blue cast on picture, then 4 or 5 diagonal blue lines with blue cast, then good picture; albeit flickering maybe 2 or 3 times a second.
The flicker seems to take the blacks in the image and give them a purple/blue tint for the duration. Whites are largely unaffected.
As I'm very close to a perfect image I don't want to mess with things _too much_ though it seems like I should investigate the Cutoff & Gain options for the Blue emitter?
I've searched for help on what these actually mean but I'm still fairly clueless.
Any suggestions?
Alasdair