Quadra Phaser clone is working!

Haible Juergen Juergen.Haible at nbgm.siemens.de
Thu Jun 26 14:49:33 CEST 1997

Started this project long ago, but it didn't work right.
Yesterday I have pulled the circuit out again, found a stupid
little component value error, and suddenly it works:

Phaser of the ARP Quadra,
14-stage symmetric transistor ladder all pass circuit,
compander system built around a CD4007UBE makes
it almost noise free.
I like it very much. I guess it would win the price for the
most efficient phaser design: only 2 transistors and 2 capacitors
for each stage !

BTW: It uses some "1N34A" diodes for signal limiting at high
resonance. Didn't find these anywhere. Can anybody
confirm that this would be germanium types ?


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