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Humming noise coming from power supply
Wir3d:
The humming noise only happens when the jamma harness is unplugged from the PCB.
its in a MK 2 cabinet btw....any solutions as to why this is happening? its more like a pig squealing noise.
Wir3d:
My neutral (white) wire coming from my power cord is getting 120V and my black (hot) wire is reading 0 on my tester..could this be a problem?
SirPeale:
--- Quote from: Wir3d on March 14, 2006, 07:29:04 pm ---My neutral (white) wire coming from my power cord is getting 120V and my black (hot) wire is reading 0 on my tester..could this be a problem?
--- End quote ---
That's backwards. White is hot, black is neutral.
No, you're hearing noise because you've taken the load off it.
Squealing from a PS isn't good in any event. Likely it has bad caps. I suggest either replacing it, or recapping it.
Wir3d:
ok, thanks peale, and ive tested the voltage on the +5v -5v +12v and there all giving me a reading of about 1.8v when powered on, so i think the power supply is bad
Ken Layton:
You have a power supply that REQUIRES a load be connected to it at all times it's powered on. WARNING: it will be damaged if you leave it that way. Either unplug the AC power going into it or connect a gameboard to that power supply now.