Hi,
Anyone know where to get schematics for repairing keyboards? The Yamaha DX21 in particular. Free would be best.

The internal switching power supply is squealing and the keyboard is not working, although the LCD screen does show something on power-up. The power supply pops out nicely, so if I knew what voltage should be coming out of the various pins I could probably fix it.

Thanks, Vudu
http://www.inthachamber.com