When MIDIfying an old equipment, it is sometimes better to leave existing wiring as they are, and just cut the old circuit boards. To simplify reconnection of old contact wires to MIDI scanner, you may now use the WIPLUG adapter, that nicely fits onto BBS-1K scanner board. Here's how it looks like then:
You need 2 WIPLUG boards to cover all 64 inputs. They accept solid or stranded wire of the size 20 to 24AWG (0.14 - 0.5mm2) and no tools or soldering are required to make fast and secure connections. The wires should be stripped at about 9mm. If this is solid wire, just push it inside untill it stops. With stranded wire use screwdriver, pen, or fingernail to push the lever down, insert the wire, and release lever.
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