I have a 25k7184 that had a vertical jump/bouncing picture of about 1/8". I could not adjust this out. The sync is hooked up correctly and I have swapped game boards and the problem is still present.
So I have tried (over the course of 3 weeks):
1. Full cap kit. All electrolytics have been replaced including B+ filter cap. (I got my ESR meter after the cap kit, would have been nice to measure the ones going in and coming out)
2. Touched up cold solder joints on main board and neck board.
3. Desoldered/soldered the wires on the main board for the remote board as they looked stressed.
4. Replaced the flyback (It had the weird black "bleeder" box on the monitor frame that was part of the flyback. It was a real pain when pulling the chassis and it had a few cracks so I swapped it out)
5. Tried 3 different remote boards to see if I had bad pots (all 3 still had the jump).
6. B+ voltage is 131 Vdc at R301 and pin 4 of IC4.
All of these have improved the picture quality (it looks REALLY good) but it still jumps! The jump has gotten better from the repairs. The monitor will run flawlessly for a few minutes, then jump for a few minutes, then go back to perfect. I have noticed that when it jumps there is a skinny horizontal wrinkle/ripple across the screen about 1" from the bottom Whenever that wrinkle is present it starts to act up. It might be a clue.
Working through the flow charts, the B+ should be 123 and if it reaches 135 the regulator should be replaced. Mine is steady at 131 (before and during jumps); would a slightly high B+ cause the pic jump? I might try swapping IC4 next.
Any other ideas out there? This is your chance to school a noob
So I have tried (over the course of 3 weeks):
1. Full cap kit. All electrolytics have been replaced including B+ filter cap. (I got my ESR meter after the cap kit, would have been nice to measure the ones going in and coming out)
2. Touched up cold solder joints on main board and neck board.
3. Desoldered/soldered the wires on the main board for the remote board as they looked stressed.
4. Replaced the flyback (It had the weird black "bleeder" box on the monitor frame that was part of the flyback. It was a real pain when pulling the chassis and it had a few cracks so I swapped it out)
5. Tried 3 different remote boards to see if I had bad pots (all 3 still had the jump).
6. B+ voltage is 131 Vdc at R301 and pin 4 of IC4.
All of these have improved the picture quality (it looks REALLY good) but it still jumps! The jump has gotten better from the repairs. The monitor will run flawlessly for a few minutes, then jump for a few minutes, then go back to perfect. I have noticed that when it jumps there is a skinny horizontal wrinkle/ripple across the screen about 1" from the bottom Whenever that wrinkle is present it starts to act up. It might be a clue.
Working through the flow charts, the B+ should be 123 and if it reaches 135 the regulator should be replaced. Mine is steady at 131 (before and during jumps); would a slightly high B+ cause the pic jump? I might try swapping IC4 next.
Any other ideas out there? This is your chance to school a noob
