This module is a variation on the 1973 Classic Serge Triple Bi-directional Router, and the 1975 Bi-directional Quad Switch modules.
The TRIPLE BI-DIRECTIONAL ROUTER is a group of three switches each of which can route one input to either of two outputs, or either of two inputs to one output according to a pulse or control voltage level. Alternately, it can be assembled to sequentially route one input to one of four outputs, or one of four inputs to one output.
The switches are true bidirectional switches. You can feed signals through them in either direction.
Note that due to the limits of CMOS, it can switch signals that are up to about +/-7 volts.
A little on how it works:
The schematic of the Triple Bi-directional Router module.
The schematic of Bi-directional Quad Switch module.
Triple Bi-directional Router.
The module uses the CMOS "Toolkit" chip, the 4007 wired as FET bi-directional switches. An LM3900 is used to condition the incoming gate signals to control the switches. A simple regulator is used to position the circuitry mid way between the power rails, at the maximum voltage at which CMOS can run (15 volts). The fourth section of the LM3900 is a part of this regulator. Note that there is no 0V/GND connection to this module.
Bi-directional Quad Switch.
This version of the circuit adds a 4013 as a two bit binary counter, and some pre-wiring to form a one to four multiplexer/demultiplexer.
|Brand||Cat Girl Synth (CGS)|
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