I built two MOTM/OMS-820 modules also. Mine are in 2U wide Schaeffer
panels I designed. I simply omitted the bypass function on the MOTM and
the pushbuttons on the OMS to compact everything into 2U. I also added
another comparator to detect "near zero" output, that generates an
end-of-cycle pulse. Patching this to the GATE input gives a new
oscillation mode: 0 to +5V, which resembles in function the famed Serge
Dual Universal Slope Generator.
Got a question for you MOTM/OMS 820 owners. Have you ever noticed an
irregularity in the period of the oscillation? I see this in both LFO
modes (the OMS original, plus the mode I added). When the period is on
the order of a few seconds per cycle, there will occasionally be a short
cycle, a period slightly shorter. It seems to happen randomly, every 5
to 10 cycles. I don't know for sure if this happens across the entire
frequency range, but it's most noticable as described. I have read
through the theory of operation on the MOTM-820 and studied the
schematic. I don't completely understand the relationship between the
control voltages and the slew rate. The OMS-820 puts the MOTM-820 to
wonderful, unintended uses! I like it very much, even including the
period anomaly, which has musically interesting applications -- another
"source of uncertainty." I have plenty of dependable MOTM LFOs when I
want a rock-solid period.
-Richard Brewster
P.S. -- Scott, your "self running" patches need to be kick started?! :-)
Scott Juskiw wrote:
>>I've just added the now-discontinued Oakley OMS-820 companion module
>>to my MOTM-820 lag processor. If you've got the MOTM-820, you will
>>LOVE the extra functions the OMS-820 adds- VCLFO and VCEG. Tell Tony
>>to reintroduce this module and sell you one!
>>
>>
>
>I agree. I have two MOTM-820/OMS-820 combos and they get used in
>every patch. I was surprised when Tony said the OMS-820 wasn't
>selling well.
>
>BTW, it's also good for manually generating a gate signal (for those
>self running patches that need a boot to the head to start up).
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