Archive of the former Yahoo!Groups mailing list: MOTM

Now that Larry is hard at work (cough cough) on the pedal interface, I'm
focusing on the MOTM-310 MicroVCO.

To refresh: this is a lower cost VCO that shares MOTM-800 EG panel, bracket,
and pcb size. That means 4 knobs
and 4 jacks.

In order to match MOTM-300 performance, and to use common parts I want to
keep it SAW-based (as opposed
to TRI-based). Looking at the pcb space and cost target ($169-179 kit) I
propose the following:

4 knobs are:

COARSE
FINE
FM (attenuator)
WIDTH (of pulse)

4 jacks are:

1V/OCT
FM
SAW
PULSE

This minimizes parts count. Having a 'blend' pot (say between SQUARE and
TRI) looks like too many parts to
fit on the board. Plus it adds $10-$15 to the cost. Since this main function
of the '310 is to 'beef up' the mix with
existing '300s, and to use as a sync generator to other '300s, this looks
like the best fit.

The only other possibility is: the 4th pots is a 'blend'. The VCO has 1 OUT.
The 4th jack is PWM IN. With no
plug inserted, the PULSE is 50%. Else, the input is a -5V to +5V pulse width
control (no input attenuation).
So you can get SAW to PULSE with the blend. This is not as gnarly as the TRI
stuff, and possibly more
musically useful.

Well??!?!?

Paul S.