Moon Patrol Monitor Ripple Wave Woes

For shits and gigs I checked out the chassis, solder pads at C365 in the horizontal sweep section were toast…ran jumpers, fixed that up. Changed from a .22 uF 400v mylar to a .15 uF 400v mylar. (I had found I liked a good middle ground between the stock .33 uF on all other Williams type A monitors and the .15 uF for greater width on Moon Patrol monitors.) I even put the horizontal centering jumper back at point 30. No change. So between returning to before my modifications to the C365 value all the way back when it was a .33 to it being a .22 when the big wave came to now it being a .15 and also re-adding the centering jumper, no difference. So I checked off "well did you break it when you did stuff?". 🤷‍♂️
 
No I haven't forgotten this thread! The hunt continues. I've now ridded the cabinet of the hybrid supply of old and installed a brand new switcher. All 4J2 wiring at the power supply now at terminals. 124 VAC to the monitor. Fully functional game still. No wave change.

Has to be chassis. No other cabinet work to be done. B+ voltage around 127. have a completely rebuilt chassis on the way. I will use this chassis as a learning experience and further troubleshoot this one on the bench. We'll see with that 4900 how things progress.
 
"New" chassis in. When in doubt, swap out. No wave, no interference, flawless picture.

So I'm going completely through the problematic one with all new caps, new filter cap, new voltage regulator, and new HOT. Then I'll put it in something else and hopefully we'll see the end of its issues!
 
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