I picked up this RD-150 last week. I has 3 keys that don’t work but apart from that it looks brand new.
Three keys on the left hand side of the keybed didn’t work so I would be required to take it apart. I was anxious to find out how the hammer action on this digital piano worked. I’ve seen the plastic hammers that are used in the (older) RD-500 and the XV-88 which I owned and those are notorious for breaking. If the hammer brakes off the key won’t come back up anymore. Here’s a picture of such a plastic hammer:
They break off at the narrowest point where the first metal ring is visible. The problem is that if you buy a Roland digital piano which has 2 or 3 broken hammers there are probably 40 more about to break.. so replace them all at once or be prepared to take the unit apart once a month 🙂
Luckily the RD-150 uses metal hammers. That probably explanes why it’s so heavy. Because if you take it apart it’s nothing more than a metal case, a very small circuitboard and a huge and heavy keybed. After removing the three faulty keys and a couple of keys around them I could see right away that someone spilled coffee or something like it on that spot. So I simply cleaned the big brown spot of dried something and the contacts around that area and reassembled it.
I’ll look up some photo’s that I made but the insides didn’t look really interesting 🙂 It works fine again though!