REQ: Phase Shifter Schematics

[Magnus Danielson]

> Hi!
> 
> can anyone tell me (or send them) where I can find the schematics
> for a phase shifter ? (cv controllable if possible)

Take a look at Leper's Effects:

http://www.wcug.wwu.edu/~jamie/schems.html

(Note, this is the NEW site since it recently rehomed)

Download the file (it's a TAR/GZIP file) and there's a lot of postscript files.
Among those you will find a file called smlstone.ps which holds the schematic
of the ElectroHarmonics SmallStone Phaser which is a quite nice guitar phaser.
It should be a quite simple task to make this thing CV controlable.

There is 4 1-pole allpass filters which are built around the CA3094 chip.
Note that the control input of the CA3094's is a current inputs. The datasheet
of the CA3094 you find at

http://www.semi.harris.com/datasheets/lin-tel/ca3094/

You migth want to make an adjustable feedback to change the characteristics of
the phaser.

You should be able to make a longer phaser section by making more coresections
of AP filters without much problem.

Cheers,
Magnus