LED/LDR VCF

[KLEIN_B at a1.wdc.com]

My Electronic Music Circuits book has a circuit for a voltage controlled
phaser using LDR's.  I used Vactec Vactrol series 5C4-2, which are dual
photoresistors in one package (with 1 LED).  This series has the resistance
range you need and the speed is pretty fair.  This is what MXR used in
their Phase 100 phaser stomp box and that I used in a Music Man guitar
amp years ago.  You can also use FET's or OTA's for VCF designs.  

The Vactec stuff may be available from either Allied Electronics or Newark
Electronics.

klein_b at a1.wdc.com