K-61 Keyboard key issue

[wjones40]

My trusty K-61 is having a problem. The "D" keys no longer function. I thought it might be dirty contacts, but no. The problem only seems to affect the "D" key, not the D#, D flat, no other keys. Any suggestions would be a help. I don't want to get rid of it because it used to belong to my wife. Do MIDI keyboards use octave splitters? Is it possible to order parts for this keyboard?

[voip]

The general arrangement in electronic keyboards is for all of the A keys to be connected to one data line, B keys to another, and so on. Then each whole octave is strobed in turn by a keyboard scan circuit, to determine which keys have been pressed. This way of doing things only requires 36 wires between keyboard and electronics, rather than the 124 wires needed for a "wire per contact" approach. From the symptoms described, the data line for the D keys is open circuit somewhere.
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