Tatsujin HUD bounces

[shmupsrocks]

Has anyone else noticed the HUD bouncing/shaking periodically in Tatsujin? I didn't notice it until I installed a new and much higher quality JAMMA extension harness and adjusted the brightness on my monitor.

[shmupsrocks]

This turned out to be voltage-related. My HAS v3.2 displays voltage in 0.02 or 0.03 increments so it goes from 4.97 to 4.99 to 5.02. Turning it down from 5.02 to 4.99 fixed the bouncing HUD. I tested it back and forth several times.

Anyone ever seen visual glitches from such a small overvoltage?

[komatik]

You know, I read this the other day when you posted it and totally glossed over the JAMMA harness part for some reason and assumed you were playing it in MAME, otherwise I would've suggested what you already discovered. Yes, I've seen many cases of CRTs having all sorts of silly geometry issues due to the signal. Most people know the issue of the image expanding/shrinking/wobbling due to changes in overall brightness, but you can also see it happen in localized regions only when it passes a certain threshold like an exponential response curve. It could be that that was just enough to push it over the edge to where it's noticeable to the naked eye.

[shmupsrocks]

I noticed another sort of tearing glitch along the sides of the LCD screen when scrolling left and right in the (vertical) game so I backed it down to 4.97v and that went away. Where can I measure what the board is actually receiving? (Any tips on how to do that with a multimeter would also be helpful.)