High pitched whistle

[SilverFerret]

Periodically my PE Bartop machine will start making a high pitched whistle of sorts. I really can't explain it any better than that. Could that be the ballast for the lighting? Game play is fine.
Thanks, Jim

[Badbaud]

On a bar top with a drop in monitor there is a plastic cover over the monitor.

Pull the monitor out of the machine, remove the plastic cover, and with a compressor blow all of the dust off of the back of the tube.

You could have some stray high voltage creep due to excessive contamination.

It could also be you high voltage lead to the back of the tube is not clamped in properly.

You could get a long flat-blade screwdriver and hold it's metal against the metal frame of the monitor as you slip the blade under the high voltage cap to discharge any high voltage stored inside the tube then peel back the rubber cap to see if the wire clip is set deep into the glass hole of the tube.

It could also be your monitor is failing and needs to be repaired, at the very least it could need a cap job.

[SilverFerret]

Thanks for the info, I'll take a look on my days off.
Jim

[EastCoastSlots]

This could also be any transformer in your game.  I've seen many times this high pitched noise caused by power supplies.  Something about the transformer causes a harmonic on the side with the gap in the frame.  My board guy solved this by wedging a small piece of plastic in to close the gap. I know that probably sounds confusing but I hope it helps.

[Badbaud]

Heck it could be a bad bearing on the phart fan. Blow it out real good with a compressor.

[cowboygames]

The flyback on the crt main board can do the same thing. We'd either push some silicone under it to close the gap or remove it and resolder snug to the board.

[Badbaud]

We use corona dope.

[cowboygames]

We used dope back in the day too, but it started to have an adverse effect on our work so we quit