Monitor Waves on Capcom Impress Cabinet

[mukuro]

Maybe someone can help me with this problem.

Equipment:
- Capcom Impress Cabinet (Japanese Import)
- Jamma SvC (tried another board too with same results)

Problem:
Just this Saturday, I started seeing the monitor wave and shake from side to side during certain types of scenes. Turns out it's only on scenes with bright backgrounds as turning down the brightness of the monitor stabilizes the image. Also, the screen will be stable during the character selection screen (SvC) at normal brightness, but a light colored background causes the whole screen to wave from side to side making everything blurry.

Scenario:
Had some people over and left the machine running for a few hours. I've never had any problems whatsover until someone came to me and said that the screen started waving around so they turned it off. At boot time and during character selection on SvC it's fine.

I tried messing with the monitor settings (V-Hold, H-Hold, etc.) and the only thing that made any difference to the waves was turning down the brightness. If I made the scren dark enough to stop the waves and did a bright colored move like a super with a big white flash, the waves would come out again.

Anybody have a clue as to what's going on here? It's been working fine for about a year.

[qrz]

a place to start - check regulated voltages , caps in power supply , etc.....
brite pics draw high beam current in the crt   

qrz

[mukuro]

Thanks for your advice! I have already replaced all capacitors  but still have the same problem, is the crt tube died?

[qrz]

possible if has much age/hours.  but......,

--BINGO! Either that, or I was attempting to say "before" but it was too many letters to type-- writing it off , check all components in the vert output stage .  small value 'lytics in the feedback circuitry
can be a source of trouble.

might not be a bad idea to check the brite limiter circuits as well.

it would be helpful to see a schematic..... hint 

qrz

[mukuro]

Crt is Toshiba, the chassis is unknown manufacturer it appear as china made low cost chassis and it is marked as GML.

[qrz]

board layout looks like hitachi tv's. and it does use an ha11??? ic which IS hitachi....

any other markings on chassis ?

not sure what the deal was with the prev post  "--BINGO! ......"   ??!!!!!!!

simply abbreviations : before= --BINGO! Either that, or I was attempting to say "before" but it was too many letters to type--    C=si (spanish)=yes   etc= eceterera  , and so forth.
in this age of creative spelling ( text messaging) it would seem most english speakers should comprehend .
perhaps, i am simply too old   

qrz