Craig Anderton's LM565 Balanced modulator

[jc]

Hi,

I'm gonna make a stab at ascii'ing Craig Anderton's first Ring Modulator
circuit because I think it's great for guitar though who knows what it'll
produce in a synth circuit ...

This version, unlike his second, is totally built using one chip, the LM565
and has no buffering but I left in the input circuit protection because
this chip will blow easy - to me this one sounds better than the enhanced
version and can be wired onto the freq pot directly (what a small mess
though !)

To the original circuit I added a switch between pins 6 and 7 which allows
for  variable lock range, a volume pot and input circuit protection as in
the second version and the VCOf pot is 100k instead of 50k (you need that
minima 2k2 resistor or the chip is likely to blow again) ...

I like to have the nulling controlled externally so that I can feed in some
VCO for special effects, this way I get a great Landing UFO sound using
this circuit and a Small Stone phase shifter  ... ... with this circuit my
guitar effect board's one step closer to being a mini-modular ... one day
I'd like to try building the Maestro Ring Mod (anybody got a schematic?!)

cheers, :)~   jc



/////// Craig Anderton Balanced Modulator //////////
                (slightly modded)


               --------------
              |   -----      |
        (-9v)-x-1|     |     |
   .22u          |LM565|     |
in-||-x-x-x-----2|     |    ---
      | | |      |     |    --- .1u
     10k| |   --3|     |     |
      | ^ v *25k |     |     |
      | D D   | 4|-    |     |
      | | |   -  | |   |     |
      - - -     5|-    |10-----------x----(+9v)-----
                 |     |     |       |              |
*(null/trim)   -6|     |9----     100kB(variable)   |
             sw  |     |             |              |
               -7|     |8----x--2k2--               |
              |   -----      |                      |
              x----------||-- .001u                 |
              |                          .22u       |
              x-----------------------||------------
              |
              |
             --- .22
             ---
              |
             10k<--- out
              |
              -