On Thu, 2009-02-19 at 05:20 -0800, Michael Hawkins wrote:
> So my idea was to patch two -5 thru +5 voltages directly onto the
> demultiplexer inputs thus bypassing all of that. And I chose -5 to +5
> because it wouldn't hurt to have the range go negative but I believe
> that 0V thru 5V should do it.
>
> And I am very disappointed that it didn't work.
>
> If I were you, I would try to find a replacement joystick unit.
>
> The range of the joystick with the bend depth pot set to max is about
> 7 semitones (or half an octave up or down).
>
> I still think that a range of 0V to +5V on those two pins should do
> the job. I am rather mystified as to why that wouldn't work.
I've actually measured it on my Poly-800, and it swings from 0 to 4
volts, not 5 volts. The opamp keeps the pitch bend voltage centred
around 2v (so that at half-scale it would go from 1 to 3 volts).
HTH,
Gordon