Asteroids thing that's always bugged me

ieure

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Pretty much every Asteroids I've ever played has this thing, where exploding objects cause a line of flickering artifacts on one axis of the display; that is, something explodes and there are faint straight lines on either the X or Y axis where the object was. It doesn't happen every time something blows up, but it does happen often enough that I notice it. It seems to happen more with objects that explode and vanish, like saucers and small rocks.

I thought it might be a monitor problem. Mine did it when I bought it, and had other monitor problems, but I just rebuilt the display and it still happens. I've seen it with other monitor-issue-having machines.

My Asteroids has a G05 in it. My Asteroids Deluxe with a V2000 doesn't do this at all.

So, is this just a thing G05s do? Is it just a thing Asteroids does? Or is it indicative of a problem on the display or the PCB?
 
Yeah, IIRC there's a few 74LS191s that I usually replace when this happens. It seems that they're just slightly out of spec or something, because it is intermittent. It's easy to check with a logic comparator, though you may also be able to narrow it down by heating/freezing the chips, or just shotgunning all the 191s that'd cause it.

DogP
 
Interesting post. I have an upright Asteroids with a G05-801 that does this with two diffrenet working Asteroids boards that were both recently repaired. I just assumed it was monitor-related, as there is a slight invisible line roll in the center of the screen as well. Nothing bad or noticible in the heat of battle, but it's there.
 
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