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Finished my MOTM-120R today

2003-09-29 by Richard Brewster

I finished assembly of my MOTM-120R today.

http://www.tellun.com/motm/diy/db120/DB-120.html

I came up with the circuit modification a while back and mentioned it on 
this list.  Scott Juskiw designed a nice PCB for it and Stooge panels came 
through with the panel.  My original mod was on a piece of perf board, and 
that is now in the parts bin, having been replace with Scott's PCB.  The 
Stooge panel looks nicer than my modified MOTM panel, which had no labels 
on the new outputs.  I also now get the AC/DC option on the outputs.

My first patch used the 120R with two MOTM-310 VCOs in the lower range with 
cross-product mode to create a pseudo-random control voltage that I passed 
through a quantizer for scaling the pitch voltage to two MOTM-300 VCOs.  I 
used the SUB1 and SUB2 outputs to gate or trigger two MOTM-800 envelope 
generators that controlled either a VCA or a VCF.  This is just the sort of 
generator I need for "no keyboard or sequencer" note patterns.

BTW, I modified my own circuit :-).  Changing R5 on the 120R daughterboard 
from 15K to 27K will scale the STAIR output to about 10V.

If anyone has built this conversion, I'd love to hear how you're using 
it.  I haven't spent a lot of time using it in the audio range just yet, 
but the STAIR output in cross-product mode looks pretty wild.

-Richard Brewster

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