Replace broken hammer key on roland kr 575 - Roland Music

SOURCE: Roland keyboard - old

Try Roland.com on the internet. It's a pretty good website and should show you dealers in your area.

SOURCE: Transported Roland KR-177, toppled - pedal assy needs replacing

Good grief! FInd a tech that knows what he is doing. You can replace the plug and/or the jack. Each is a few dollars at most. You can even do it yourself. If you can see where wires went just buy new parts. They are probably available even at Radio Shack.

Testimonial: "Good advice, but someone who examined the carnage said there were either four or five wires (can't recall) and the plug to the machine has eight pins."

SOURCE: My Roland Rd-500 has no sound....the factory demo

You either did not get the ribbon cable seated OR got it upside down.

If this cable is the flat ribbon with exposed solder plated points of contact, OFTEN those connectors have a latch to release by GENTLY moving tabs on eaither side in the direction of pulling the cable out. This lock MUST be moved out slightly to allow the cable to seat properly. The solder plated contacts will be FULLY into the connector when seated properly.

These cables ALSO can be inserted backwards and NO connection will be made.

SOURCE: How do I remove the keys from a Roland KR 4700

If these are semi weighted keys here is a cut and paste from a manual:
19. Disassembling the Keyboard Assembly
* After inserting a round stick (Rod: TX000670)
between the frame and the keys, remove the
circuit boards. (Fig. 23)
19-1 GHD EBUS L, MK SUB Circuit Board
(Time required: about 12 minutes)
Remove the seven (7) screws marked [260A]. The
GHD EBUS L and MK SUB circuit boards can then
be removed. (Fig. 24, Photo 5)
19-2 GHD M Circuit Board
(Time required: about 12 minutes)
Remove the five (5) screws marked [260B] and the
screw marked [262]. The GHD M circuit board can
then be removed. (Fig. 24)
19-3 GHD H Circuit Board
(Time required: about 12 minutes)
Remove the four (4) screws marked [260C] and the
screw marked [262]. The GHD H circuit board can
then be removed. (Fig. 24)
* Keys can be removed without removing the
circuit boards.
* After removing the GHD EBUS L, GHD M and
GHD H circuit boards, and the rubber contacts
can then be removed.
19-4 Rubber contact
Remove the GHD circuit board for the involved key.
The rubber contacts can then be removed.

The rod is inserted above the weighted hammer and the bottom of the keys from one end. It appears to be about 1/4 inch diameter dowel and will run the full length of the keyboard. You might use 3 foot ones from each end.

Screws are removed and the boards removed without taking the individual keys out.

Testimonial: "Thank you for taking the time to help. Can't wait to get it fixed, thanks to your helpful information. I really appreciate it."

SOURCE: We took our roland

The motherboard is probably not available... You haven't mentioned any symptoms of the problem you are having. Some service centers really don't want to be bothered and give up too easily.