G05 looks like a plasma panel

Bullwinkle

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Hi,

Im working on an asteroids that plays blind. I've put 2 boards in and both do the same thing. I've checked the AR and the voltage is 5.2 and 12.01vdc.

The monitor displays what looks like one of those plasma balls you see in a laboratory. Any ideas what I need to look at? Is this a capkit issue?

Thanks,

Tom
 
Let's see a pic? Sounds like your brightness and/or contrast is up to high...
 
Although that usually indicates a board issue, I have a deflection board that does something similar. I haven't had a chance to work on it yet though as I had a spare working one on the shelf...
 
Any chance you (or a buddy) have another vector game (or oscilloscope) you can test the game boards on? Then you can verify board vs. monitor issue. It does look like the game PCB is spitting out garbled vectors to the monitor, but you are right, it is weird it would do it to two separate game PCBs.

If it ends up being a monitor issue I would do the following: Recap deflection (including two main caps) and HV board, replace brightness and contrast pots, re-flow all header pins on both boards, replace output transistors on monitor frame and then retest.
 
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Any chance you (or a buddy) have another vector game (or oscilloscope) you can test the game boards on? Then you can verify board vs. monitor issue. It does look like the game PCB is spitting out garbled vectors to the monitor, but you are right, it is weird it would do it to two separate game PCBs.

If it ends up being a monitor issue I would do the following: Recap deflection (including two main caps) and HV board, replace brightness and contrast pots, re-flow all header pins on both boards, replace output transistors on monitor frame and then retest.

Yup..going over to a friends this evening (or soon) to test the board in his asteroids.. where I have 2 boards doing the same thing, i wasn't certain it was a board issue as they do play blind.
 
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For those following this thread, EVERYBODY was right to an extent :) There is an issue with both the monitor AND the board... gotta love it. When I placed the board in a known working machine, it displays the picture but it seems to "roll". by that I mean, the picture seems to make a cylindrical shape and the shape rolls. Was told to look at my DACs. I'll be placing the monitor in soon to test to see what I get with a known working board.

Thanks
 
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