EM Moog Filter

Dan Higdon hdan at charybdis.com
Tue Feb 27 04:49:17 CET 1996


> From: 	gstopp at fibermux.com[SMTP:gstopp at fibermux.com]
> Betcha it'll work fine on plus/minus fifteen, maybe need a little 
> component change to keep the scale factor to 1v/oct or something. More 
> study required.

Worth a try.  Seems I might need to change the top divider resistor on the ladder
to maintain the right "rung voltages".  Or is that mostly irrelevant, as long as they
are proportional?

>     I fergot to look - do they offer a PCB???

No PCB; they suggest vectorboard or some other prototyping board.  In fact,
the author made the point that this design is stable enough for such
"slipshod" construction (my words, not his).  I was thinking that maybe
I would breadboard this baby (if and when I ever get time to play with
electronics again :-\)  with the specified values, and substitute trimmers
for v/oct as per Jansen's schematic.  Maybe the resulting hybrid design
would work.  (I'll gut the "vca" in EM's version most likely.)

BTW, has anyone built Rick's schematic with different transistors?
He specifies BC109(a,b,c)'s or something like that, and somewhere I got
the impression that those are a little pricey/hard to come by.

Later,
Dan Higdon (hdan at charybdis.com)




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