Roland U-20 RS-PCM Keyboard (#1)


My first project 🙂 I bought this 1989 Roland U-20 for 20 bucks in Amsterdam. Problem was the keys didn’t work. I thought it would be cool to take apart and try to fix it.

U-20’s with keys that don’t work is very common. If you google this model or look at online auction sites there is always a U-20 for sale with this problem.

I’ll write some more about repairing this synth later.

I think this is a very underestimated synth. It’s very limited in it’s capabilities and it’s a rompler (plays back recorded sounds instead of creating sound) but it sounds VERY GOOD! I even like the piano sound and it’s got some very powerfull strings. In my opinion (and I’m writing this in 2015 after having taken apart a couple dozen Rolands) this synth is built very well. It’s made of steel instead of plastic (and yet only weighs 8 or 10 kg) and it has one of the best playing keybeds you’ll find in a synthesizer. It’s semi weighted and it has aftertouch. It’s the same keybed used in Roland’s D-70 and JD-800 for example. Compared to this synth the 2005 JUNO-D looks and feels like a plastic toy. This is a pro quality instrument built to last an eternity.

Use this thing as a midi controller for a while and you will never play your shitty Edirol or M-audio controller ever again 🙂 (well you’ll only miss the gazillion assignable knobs and sliders on those)

I’ve cleaned the contacts on mine only once and it’s been working fine ever since.. even if I don’t use it for a couple of months everything works fine everytime I power it up!

Here are some pictures of the repair:

This was the first synthesizer I took apart and I still have it today (2015).

This is what I repaired:

  • Removed the red glue holding the weights in the keys
  • Cleaned the contacts underneath the keys because only 3 keys worked!
  • Replaced a few tact switches underneath the buttons
  • Glued a patch wire on the flexible PCB because the top 5 keys didn’t work.

I did the exact same repair with the patchwire recently on my JD-800. I have this U-20 for 3.5 years now and it still works fine. Only the aftertouch needs quite a bit of force but I’m planning on fixing this as well. I recently found a nice tutorial and a very cool website with a lot of U-20 information including a ton of patches I’m eager to try out 🙂

The U-20 is a true quality instrument. Looks great, sounds great, plays great. They are practically free now a days. I have 2 and I paid 20 euro’s for each of them.

This site contains a lot of info on the U-20:

7 thoughts on “Roland U-20 RS-PCM Keyboard (#1)

  1. Hi,
    I’m searching for an E/B key for a roland XP-50. Can you help me with this, I live in Belgium.


    1. Sorry, don’t have those but contact Roland Belgium or any music store that sells Rolands and ask them to order the key for you. In my experience the keys cost around 5 euro’s each and Roland will still sell you keys for older synthesizers.. shouldn’t be a problem.

      grtz, Jorick


  2. Good morning,
    I am trying to repair my U20; Could you give number keys placement. There a lot of differents key (CF21, CF22, CF23, …). I dont’t knwo where to place it.

    Best regards


    1. Hi Steph,

      The numbers don’t mean anything (other that being a mold number) so CF21 and CF22 are the same. CF means it can be used as a C or an F. First put all the black keys on the frame. They are all identical. If you look at the top holes you hook the keys in you will see groups of 2 then 3, then 2 then 3 etc. That’s where the black keys go. The white ones start with C, then D, E, F, G, A ,B and then C again. Repeat. E and B are also identical.

      Regards, Jorick


    2. For reference, here is a link to an image on the U-20 Homepage which shows a key sequence. I will agree with Jorick that the keys appear to be in random order when assembled at the factory and the numbers are just mold markings. The solitary oddball key of course would be C’11 (Upper C)


  3. Hello Jorrick,

    I am in the middle of repairing a Roland U-20 with the same problems you have discribed. Only 3 keys are working. After i removed the keyboard from the synth case, i saw the terrible keyboard to mainbord connection. One of the previous owners has distroyed the connection and tried to repair it with a lot of pressure from cartonboard pieces and tape, with of course no result.

    So i have to do the same repair you have discribed with the D70 topic. So i will glue the wires to the keyboard PCB. But i can not figure how to connect these wires to the flatcable which goes to the mainboard. Did you have the same issue with the U-20 or only with the D70? I saw with the D70 you are using at PCB where the flatcable can be connected and where you soldered the wires from the keyboard PCB. There is no such board in the u-20. Any idea’s on that? Glueing the wires to the flatcable? Is that strong enough?

    André Pascal.


    1. Hi André,

      So the connector at the mainboard is broken? Is the flatcable still intact? What I did with the D-70 is solder 16 wires on the backside of the circuitboard where the connector is. I think you can do the same thing with a U-20 as if I remember correctly the connector opposite side of the PCB when you have the U-20 turned upside down. The hard part is glueing the 16(?) wires to the flatcable or the connector at the left side of the keybed if you remove the flatcable. The U-20 I have just needed cleaning of the contacts because only a few keys worked. I had to solder 1 bypass wire to the connector at the mainboard because the top 5 keys didn’t work. I can remember that plugging the flatcable into the mainboard correctly was not easy. I had to open the U-20 up several times before I got it right..

      Regards, Jorick


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