I've been asked to help repair a keyboard. On examining the keyboard I found the issues (circled) in the below image:
- A tear in the middle of the ribbon cable
- A tear across the end of the short side of the cable where it entered the PCB connector
My original idea to repair this was to desolder the left side, buy a replacement ribbon cable, and then resolder and connect it. Unfortunately I've been unable to locate a replacement part.
My only other idea is to remove the insulation over the smaller tear and solder on small wires to bridge the tear. Then to remove the insulation on one side at the end and attempt to reinsert it into the PCB connector. Given the size of this cable I doubt my ability to solder the cables to rejoin them.
Does anyone else have any suggestions for an alternate method of repair?
Best Answer
Removing the insulation in a reliable way might be very difficult. It may be impossible to have all ffc contacts work at the same time. Also, the cable will be shorter after this operation. Will the length be sufficient after mounting?
I'd try to get a ffc-cable with the pitch of the connector on the right and long enough to make all connections on the left. You have different options then.
One is, to cut the flat cable along its lenght on the left side, so that every trace has some cm for its own. You can then fold bend and trim the traces to meet the soldering points on the left PCB with minimized deviation and stress. Removing the insulation is neccessary, too. But you see, if it's sufficient when you try to solder it.
The other is to extend a complete FFC cable by soldering braided insulated wires to the left side. These are easy to connect to the left PCB.