[sdiy] Rotary encoder

[Louis van Dompselaar]

I seem to have been mistaken in being mistaken about turning
3x4 rotary switches into a marix.  At least some of them.
I just looked at a Lorlin 3x4 and that just needs the stop
removed to turn it into a 12-step switch.  If you then
connect:
  1-5-9 to Y1
  2-6-10 to Y2
  3-7-11 to Y3
  4-8-12 to Y4
and
  A to X1
  B to X2
  C to X3
it should probably work with he 74C922.

Come to think of it, if you connect that to Ken Stone's
circuit, you get a circuit that lets you select every
note in an octave without needing the 12 trimmers that
for example the Yusynth Standards needs.