Monitor problems

[XYXZYZ]

Okay, I have a Zenith.... something; the part with the model number is worn off. The cabinet was apparently dedicated Killer Instinct in the beginning, and I assume it's the original monitor. (Did they have a standard monitor?)

Anyhow, the first problem is intermittent blurriness. Every now and then the picture is nice and clear, but it's usually very blurry. Fiddling with the contrast/brightness etc. doesn't accomplish much.

The second problem is that whenever the game displays a very bright screen with lots of white, (The character drawings in Golden Axe's attract mode for example)  the picture goes nuts and jumps around a lot.  Often after the white screen jumping is finished (when the game displays a darker picture) it will either "fix" the blurriness, or be very blurry when it was sharp before. Usually it'll be blurry, though. And when the game goes from bright to dark, the picture kind of shrinks in a little.

The thrid problem is the far left side of the screen is blank, adjusting the horizontal position causes the picture to disappear into the blank spot rather than scroll to the actual edge of the screen.

I have done a partial capkit replacement, there are a few 160V caps and a  200V / 560 µF cap I couldn't find but I have some on order and I'll be able to finish it later. The caps I did replace (18 out of 22) didn't seem to change anything, though.

oh, and currently there's an Xbox connected to it via Ultimarc's Xbox > arcade monitor adapter, but the monitor problems are the same with arcade boards.

Thanks for any help.

[grantspain]

sounds like the flyback breaking down to me,going out of focus and jumping

[XYXZYZ]

The flyback has those two knobs on it, the one on the bottom seems to control brightness, and the one above it does nothing. Is that another sign?

[grantspain]

i think you have a wells gardner u5000 chassis,you can id your chassis at www.jomac.net.au
i do think the flyback is breaking down as the pot that is not doing anything is the focus
you should check for dry solder joints or bad circuit board track first as these monitors were renowned for bad connections especially on the neck board which is where the focus line goes and around the flyback

[SirPeale]

Is there a way you can post a picture?

[XYXZYZ]

I can, but not until Monday at the soonest.