I recently bought a Yongmei YM7000 keyboard on TradeMe that was earthquake damaged and not going. I got it for $9 and bid just out of interest, thinking I could probably get it going and give it to someone for a learner keyboard. There were two faults, one being a wire had come adrift in the wallwart - easily fixed. The other proved more elusive. The end of the main circuit board was torn beside the LSI. I actually got the thing working, then remembered I had forgotten to vacuum the broken bits of plastic out, so I took the top off, and it stopped working. No amount of coaxing, and resoldering would get it going again, so it's off to the trash. Here's of photo showing why this cheap junk is irreparable - The LSI is on a little piece of circuit board that is inside a hole in the main board, and it is just solder bridges making contact between the two boards. It would seem the brain of the thing was made for something else, and then spliced into this model.