jbbradley
Member
Power up the Vanguard, original board, whines for 5 min then stops. High pitched constant sound that doesn't let up till it's done. OK. Thought it was the board or maybe a capacitor on the board so I got another from quarter arcade. Got the new board, same thing. Except I have the added benefit of missing maze walls after it's on for 30 min
So I check the power supply and I'm getting 6V on the +5v. So I adjust down a bit..garbage on the screen at 5V. Up to 5.5V, everything works fine except the whine never leaves and I've now got a hum bar effect. So, I'm thinking I have a bad switcher maybe. Any ideas?