Tempest video issue monitor or pcb?

KevsArcade

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Anyone know is the extra lines are a pcb or monitor issue?
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Could be either, but more likely monitor. First try turning down the brightness using the SCREEN knob/control on the back of the HV cage on the monitor.
 
Ok, that helped. Turning the brightness down until the blue cut off removed the lines. It just showed red and the lines where gone. Problem is related to the blue and there is no green. This monitor did look great with a working Space Duel cab plugged into it so I'm still not sure what to think.

Any ideas on the 2 stuck switches shown on the first test screen? One is for center coin mech but there's no short on the door and the switch shows stuck with the door unplugged. No idea what the switch in the top row even is. Also when on the first test screen, there's a constant high pitch tone.
 
You can balance the individual colors using the bias and drive controls on the neck board. Note also depending on which revision neck board you have, there may also be an extra pot on the neck board to control brightness as well.

As for the sticking buttons, it can be a stuck switch, but also potentially a bad or broken component on the aux board, or possibly also a bad Pokey chip (also on the aux board). See the schematics, and look at the resistors and caps on each input, which are located on the aux board, as these often get smashed, and/or the caps can go bad, and cause stuck switches.

If any switch is pressed (whether legitimately, or if there is a problem and the board just thinks it's pressed), you will hear a tone, hence the constant tone you're getting.

You can try reseating the pokey chips (carefully, so as not to bend any pins). You can also try swapping them with each other, and seeing if that changes the behavior at all. Note you may see one problem disappear and a different one appear, depending on which Pokey is bad, and how it has failed. You may also get P or Q errors reported in test mode (which indicate a bad Pokey, though they don't flag all possible types of failures.)
 
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