K4600 monitor "resets" after power off?

[texasmame]

This is occurring on a Defender.

I turn the game on and the screen is a garbled mess. Adjusting the H hold pot and L351 allows me to get it to look as good as the pic attached shows; all good except for the top 25% or so of the screen.

Then, when the game is turned off and turned back on - back to garbled mess and have to readjust once again??? The game being powered on and off should not affect the monitor settings.

ROM and RAM tests all pass. Could this be a video decoder issue?

Suggestions?

 

[texasmame]

Have narrowed this down to an issue on the VER/HOR card - swapped in one from Galaga, adjusted, and it's fine and retains the settings.

Off to get some caps and R360. . .

 

[KenLayton]

Some capkits don't include ALL the electrolytics for the hor/ver XY board. The kits from Zanen Electronics do include them all.

 

[texasmame]

Went by the kit listed here and got just the XY board caps listed, and the R360:

http://arcarc.xmission.com/Tech/Cap Kit Info/Zanen Cap Kitc201a WG K4600.txt

Lucky enough to have a great little mom and pop electronics store nearby that has very good prices and just about every component you can think of.

 

[texasmame]

Looks like R360 was the problem.

Take it out - no picture at all.

Replace with known good - top curl gone.

Weird.