[sdiy] Ring modulator and power supply questions

[john mahoney]

Hey, that's not a real ring modulator, that's an ARP Odyssey-style,
Exclusive OR (XOR) pseudo-ring modulator! Not that there's anything wrong
with that. :-)

Changing the two 100K resistors on the left side to higher values will allow
more signal to pass through. You can install trimpots or front panel pots if
you want to have adjustable trim.

Also -- and I don't know if this matters -- but my assumption is that these
XOR circuits are designed to modulate pulse waves. Feeding them other
waveforms may or may not work as well. But I'm really not very sure about
that.
--
john


----- Original Message ----- 
From: "Rutger Vlek"
>
> i'm building an analog synth containing a version of the SBM RingModulator
> (http://www.ele4music.com/pdfs/sbm.pdf). I'm running it on 15V instead of> 12V and it works fine except that the input's have to be very high to get
> the thing working! Plugging the VCO's into it doesn't work, but boosting
> them through a mixer first does work. What is the simplest way to get the
> input threshold of the RingMod down or the inputsignal up in volume? I'm
> using the latest Oakley VCO's.
>
> Another question is about power supply. I run my synth on 15V but i have a
> keyboard i want to build in that runs on 12V (originally it was an
Evolution
> MK149). What is the simplest way to convert the 15V to 12V? Does someone
now
> a circuit that can do this? Or can the Evolution handle the 15V?
>
> Regards,
>
> Rutger
>