While using my computer I suddenly lost the green color on my Panasonic SL90 monitor. Can anyone suggest where to start checking, or does anyone have a schematic for this monitor?
thanks G.M. Durrence (To reply remove -nospam)
Faulty cable or connector maybe?
That's the first thing I'd check.
Dave
Checked all that, also checked all ribbon cable connectors. Even the menu doesn't have green so this eliminates cables and connectors. I also made sure the CRT was socketed well. I suspect an internal CRT problem but would like to test voltages on the CRT before discarding it I but need a schematic.
G.M. Durrence (to reply remove -nospam from address)
change the green drive wire, at the crt socket, with one of the other colors and see if the green comes up. If it does then the crt is probably ok.
You don't need a schematic for that. You have three identical video circuits so comparing voltages, preferably with a grayscale or white display on the screen at the time, should be straightforward enough. If the green channel measurements differ significantly from the others, chances are there's a bad component on the CRT base PCB, ie video amp IC, open resistor, bad driver transistor etc. It could also be a cracked solder joint, particularly on the CRT socket. If the R, G and B cathode pins on the CRT are all giving similar readings, then the green gun on the CRT has probably failed catastrophically- it happens sometimes.
There's freeware pattern generators on the web which will display appropriate patterns to help you.
Dave
Green is the closest pin to the left hand side facing, so it could even be that the cable connector is not screwed in sufficiently.
Tom
??
Tom
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