[sdiy] modding for LFO retrigger

[Samppa Tolvanen]

On Wed, Jul 16, 2008 at 12:21 PM, Mark Rivera <marr at lumin.us> wrote:
>
> General question since I have only general knowledge about the intended
> target LFO..
>
> Are all LFOs topologies designed such that poking a particular place in them
> with 0V or 5V (or similar) will cause them to retrigger (i.e., reset the
> cycle)?
>

It depends. Can You identify the circuit topology? With sawtooth and
triangle (witch can be derived from each other) it's hard ot tell what
it is in Perfourmer. Open it up ;)

If it's sawtooth core, You'll probe around the reset circuit and add
"normal" hardsync there.. for Tri-core, someone who knows something
comes up with the idea ;)


> I thought maybe this could be achieved by adding a small PIC-based
> sub-circuit which would add a second MIDI input listening for clock ticks,
> and a switch for selecting 16th/8th/4tr or similar retrig times. Retrig
> would be affected via a DG403 analog switch (?).

Or You could just tap existing midi input after the opto. Sounds very
doable and fun. (me likes predictability and repeatability)

Samppa