[sdiy] How do duophonic keyboards work?

[Pete Hartman]

I re-read the Ody manual a bit and it has to do with the current generating
circuit being used to also generate that differential voltage.  It's
driving a constant current through the resistor chain of the keyboard (such
that each resistor drops 1/12 V for each key).  When you close two keys,
you're effectively short circuiting the resistors between the two keys.
Since the circuit is generating a constant current, this changes the
voltage output proportionally to the part of the circuit being cut out, so
that current is maintained with the smaller number of resistors.

Pete

>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20250802/51ec3c59/attachment.htm>