Wg 4600 scrolling issue, please help.

[abispac]

So I scored a free wg 4600 that works just fine, with great image and color. It's super dirty, and I'm afraid of cleaning it up with water and soap, so I still got to work on that decision. Anyway, the owner had me install an LCD screen because this monitor was scrolling up and down. So I took it home and would like to use it for my cab. I can get a stable image, but it starts slowly scrolling after a while. I'm using a pi4 with a vga666 and a Vga breakout cable, works just fine on my RGB-moded tv. On Facebook, someone advised me to check on the solder joints, and they look fine. Im not sure what kind of sync signal the pi4 with recalbox 15khz outputs, but on the RGB moded tv I use the trick where you put together both sync cables, and sync works just fine. I tried the same on the wg4600 and attached the cables o the separate negative sync pinout. That's how I have it right now, I had not tried something different. So I wonder if someone with experience in these monitors would help me out. Do I have it connected correctly? thanks for your help.

I also had this advice from facebook.

There's a good chance it's just bad solder joint or potentiometer (pot) opening and closing as it heats up and cools down. Reflow any edge connectors, pins, wires in through holes, and pot legs on the PCB's/daughter board and see if the problem persists. If the pot adjustment is very sensitive and the smallest change will cause the screen to roll, there's a good chance the monitor does doesn't know how to handle the composite input. Which is common on older monitors like the G07 & WG4600. Easy fix is to run separate Horizontal & Vertical instead of running a Composite input. A lot of the times there will be a loop going from the Horizontal & Vertical Sync on the monitor input connector, usually a white wire, that I'll cut and will stabilize the Sync on a monitor with a sensitive Sync Pot. Which was a pretty common mod back in the day on Bally & Midway Games while doing a game conversion.

[lilshawn]

this monitor is well over 30 years old now and likely needs a pile of capacitors that deal with screen drawing timings replaced.

in a crt monitor like the 4600 there is a raster adjustment jumper that can be installed in 3 different positions. if it's in the middle position, try moving it to either left or right, then adjust the vertical position pot back to center it again to see if it will stay stable. if it's already on one of the outside ones, try moving it to the middle position.

if not, it's cap time.

[abispac]

this monitor is well over 30 years old now and likely needs a pile of capacitors that deal with screen drawing timings replaced.

in a crt monitor like the 4600 there is a raster adjustment jumper that can be installed in 3 different positions. if it's in the middle position, try moving it to either left or right, then adjust the vertical position pot back to center it again to see if it will stay stable. if it's already on one of the outside ones, try moving it to the middle position.

if not, it's cap time.

Thanks, actually, conecting the sync cables separately and a good clean did the trick, but then it started giving problems with colors and focus, i didn't wanted to spend much time, so i tossed the monitor away.

[Zebidee]

Thanks, actually, conecting the sync cables separately and a good clean did the trick, but then it started giving problems with colors and focus, i didn't wanted to spend much time, so i tossed the monitor away.

What a waste, esp. after replacing with a LCD. Probably just needed a capkit. A little bit of TLC could have gone a long way