Moved from this topic to improve exposure to members.
Hitachi SuperScan Pro 800
20" Color Monitor
Max resolution: 1600x1200, 60-75Hz
Model: CM800U
According to ex-owner, monitor had a picture shrinkage problem that had gone on for some time. It made a click sound and would pull in from the sides. I know the sound well because I have the identical monitor. It is a relay, and in mine I get the click sound and the same result, reduced horizontal sweep. It seems a tap on the case clears the problem so I'm certain it's a cold joint or loose connector somewhere. Okay, back to the victim...
While using the monitor one day, it suddenly went *pop* and went dark. Power indicator lamp stayed steady on. Cycle the power and it makes the degauss noise, but remains dark.
Okay, I inherit monitor and get it on the bench. Let me say this is a beast and it is a technicians nightmare. Five (5) shield panels must be removed to get to the chassis. There is a large 11" x 14" panel that holds a microprocessor board standing vertically and plugged into the mainboard at the rear. While connected, the only chance for access to the components is over the horizontal output section, straight down from the top or from the underside of the mainboard. The mainboard is completely outlined in a plastic guard/insulator that comes up past the edge of the board and extends into the solder side a full inch. There is no access to this area of the board without removal of this "guard". There is no moving the unit on the bench without assistance, as you have exposed components at the edge once the guard is removed. So here it sits, on its side.
Diagnosis continues in next post...
Hitachi SuperScan Pro 800
20" Color Monitor
Max resolution: 1600x1200, 60-75Hz
Model: CM800U
According to ex-owner, monitor had a picture shrinkage problem that had gone on for some time. It made a click sound and would pull in from the sides. I know the sound well because I have the identical monitor. It is a relay, and in mine I get the click sound and the same result, reduced horizontal sweep. It seems a tap on the case clears the problem so I'm certain it's a cold joint or loose connector somewhere. Okay, back to the victim...
While using the monitor one day, it suddenly went *pop* and went dark. Power indicator lamp stayed steady on. Cycle the power and it makes the degauss noise, but remains dark.
Okay, I inherit monitor and get it on the bench. Let me say this is a beast and it is a technicians nightmare. Five (5) shield panels must be removed to get to the chassis. There is a large 11" x 14" panel that holds a microprocessor board standing vertically and plugged into the mainboard at the rear. While connected, the only chance for access to the components is over the horizontal output section, straight down from the top or from the underside of the mainboard. The mainboard is completely outlined in a plastic guard/insulator that comes up past the edge of the board and extends into the solder side a full inch. There is no access to this area of the board without removal of this "guard". There is no moving the unit on the bench without assistance, as you have exposed components at the edge once the guard is removed. So here it sits, on its side.
Diagnosis continues in next post...
Comment