Asteroids Deluxe playing blind

manadams

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no spot killer and have neckglow on 19V2000 monitor

Things I have checked and done:

reflowed soldier on headers
removed r100 and r101 and installed jumpers
checked voltage coming from power brick
checked frame bottlecap transistors

I have read that on these monitors you can have neckglow even if flyback is bad

any suggestions on where to look next?
 
You could possibly have an issue with your game board, though if your spot killer is out, then that's far less likely. But I wouldn't rule it out completely unless you can verify it either with a scope, or by testing the game board in another cab.

Do you have HV? You should be able to maybe hear it, or definitely feel it as static electricity on the front of the tube, when the monitor is on.

Recap and reflow the HV cage, if you have not done so already. Also, you could have a bad HV diode.
 
Yes you can have neck glow independent of the HV board, as the 6.3v heater (and coin door light) voltage comes directly from the power brick.

I'd also recap the deflection board, as that is where the Z amplifier and spot killer circuits live, and their mission in life is to control the brightness of the vectors. If you hear deflection 'chatter' and can get an image by turning up the brightness and contrast, then that would really point toward these circuits. It could be more than caps though - a bad transistor or even the LED itself.
 
Douglas has a good point about the spot killer circuit and/or LED possibly malfunctioning. You can check this pretty easily, by watching the LED while pressing the reset button on the game board.

If you press and hold the reset button for a couple of seconds, you should see the spot killer LED come on, then go off again when you release the button. If that's the case, it's a fairly good probability (though not 100%) that you're getting deflection, and the spot killer is ok.

He also has a good suggestion about cranking the brightness and contrast up all the way, and seeing if there is any image, as you could have an issue with the Z output of the game board also. (Or the Z section of the monitor.)

It would be really helpful if you had temporary access to another working Asteroids or AD PCB, just to narrow down the board vs the monitor.
 
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