Black Matrix
Well-known member
Monitor Gurus: Sanyo 20ez working(almost) slight ripple
Hey all,
Still repairing this bane of my existence and its almost working with the help of the group. So here's whats been done.
1. Cap Kit
2. large Filter Cap replaced
3. some broken pots replaced
4. flyback replaced
5. IC601 and HOT replaced
6. 2SD1090 Current Limiter replaced
After my previous rounds of repairs, I had the monitor unadjustable in the high 130s so I replaced the the IC601 and HOT.
Hooked it up and powered it up and I was getting a white flashy screen so I tried adjusting the B+ pot. Metal screwdriver slipped and touched something in the near area and sent it into HV overvolt protection. Powered down, and back up again. The monitor was back up so I adjusted the bright and saw that the pic was rolling. Adjusted the H-hold and got it zeroed in. Now I have a pretty good pic. But I do have a mild ripple in picture across the vertical of the monitor (like a little wave that runs across the girders). Also, I can't get the B+ to adjust down to 108. I think its fluctuating around 109 is the best I can do. And on the other monitors, adjusting the B+ would send the voltages above and below the target 108, this one just doesn't go low enough.
So I suspect that my tragic slip of the screw driver may have damaged either the B+ pot, or one of the surrounding resistors. But if it was a resistor, would it even have a picture. And it could be a cap, but I doubt its the filter cap which would be the first suspect following the flow chart. Already replaced it....but maybe my slip damage it? I know I'm going to have to pull the chassis again....for the 5th time to look for things. But I wanted to ask the monitor guru's first to see if they had any ideas first. SO...anyone know what causes a slight voltage ripple and slightly high B+ voltage. Many thanks in advance.
And while its probably normal, I have gotten a couple overvoltage protections shut downs when trying to adjust the B+. It would shut down and the b+ would shoot up to 134.
Hey all,
Still repairing this bane of my existence and its almost working with the help of the group. So here's whats been done.
1. Cap Kit
2. large Filter Cap replaced
3. some broken pots replaced
4. flyback replaced
5. IC601 and HOT replaced
6. 2SD1090 Current Limiter replaced
After my previous rounds of repairs, I had the monitor unadjustable in the high 130s so I replaced the the IC601 and HOT.
Hooked it up and powered it up and I was getting a white flashy screen so I tried adjusting the B+ pot. Metal screwdriver slipped and touched something in the near area and sent it into HV overvolt protection. Powered down, and back up again. The monitor was back up so I adjusted the bright and saw that the pic was rolling. Adjusted the H-hold and got it zeroed in. Now I have a pretty good pic. But I do have a mild ripple in picture across the vertical of the monitor (like a little wave that runs across the girders). Also, I can't get the B+ to adjust down to 108. I think its fluctuating around 109 is the best I can do. And on the other monitors, adjusting the B+ would send the voltages above and below the target 108, this one just doesn't go low enough.
So I suspect that my tragic slip of the screw driver may have damaged either the B+ pot, or one of the surrounding resistors. But if it was a resistor, would it even have a picture. And it could be a cap, but I doubt its the filter cap which would be the first suspect following the flow chart. Already replaced it....but maybe my slip damage it? I know I'm going to have to pull the chassis again....for the 5th time to look for things. But I wanted to ask the monitor guru's first to see if they had any ideas first. SO...anyone know what causes a slight voltage ripple and slightly high B+ voltage. Many thanks in advance.
And while its probably normal, I have gotten a couple overvoltage protections shut downs when trying to adjust the B+. It would shut down and the b+ would shoot up to 134.
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