thegnome
Member
Ok... I just picked up an UMK3 machine with some monitor issues. Unless you turn the Green Drive Pot all the way up, the machine doesn't display green and with the pot turned up all the way it doesn't display black, but grey-green where black should be. The monitor has not been rebuilt and will be as soon as I can get a cap kit and flyback [there's a hairline crack in the plastic housing of the flyback so I'd rather replace it while replacing everything else].
My question is: What would cause the behavior that is exhibited by this monitor? Could it be a bad Pot/Transistor on the neckboard? Bad Caps? I *really* want this machine to work as soon as I can get it to, because well... I love MK!
I snapped some photos of the boards monitor test screens to help aid in diagnosing the problem, as well as a couple shots of the neckboard and tube.
So here we go...
Test screen menu [you can see the colors are a little out-of-whack]
The "RED SCREEN"
The "GREEN SCREEN" [You can barely see the slight green tint in the black, it's a little more pronounced in person]
The "BLUE SCREEN"
The "COLOR BARS" Screen [Notice the lack of green]
The "CROSSHATCH PATTERN" Screen
Current settings of all the neckboard Pots [From Left: Red CutOff, Red Drive, Green CutOff, Green Drive, Blue CutOff, Blue Drive]
Shot of the tube [Shouldn't there be convergence adjustment rings?]
My question is: What would cause the behavior that is exhibited by this monitor? Could it be a bad Pot/Transistor on the neckboard? Bad Caps? I *really* want this machine to work as soon as I can get it to, because well... I love MK!
I snapped some photos of the boards monitor test screens to help aid in diagnosing the problem, as well as a couple shots of the neckboard and tube.
So here we go...
Test screen menu [you can see the colors are a little out-of-whack]
The "RED SCREEN"
The "GREEN SCREEN" [You can barely see the slight green tint in the black, it's a little more pronounced in person]
The "BLUE SCREEN"
The "COLOR BARS" Screen [Notice the lack of green]
The "CROSSHATCH PATTERN" Screen
Current settings of all the neckboard Pots [From Left: Red CutOff, Red Drive, Green CutOff, Green Drive, Blue CutOff, Blue Drive]
Shot of the tube [Shouldn't there be convergence adjustment rings?]
