Catgirl Synth Pulse Divider, Gated Comparator, Quad Logic Gate

CGS digital panelQuantity: 1 each of these in one physical panel of 32 jacks

From Ken Stone’s CGS website:

Pulse Divider

This module consists of a pulse divider with integer divisions between 2 and 8. The divider is used to generate interrelated pulses for use in creating poly-rhythms, and unusual sequences. It can also be run at audio frequencies as a sub-oscillator/sub harmonic generator. The output pulse from each division is one clock cycle in length, and the relationship between pulses is fixed. Specifically, the /4 output will correspond to every second pulse from the /2 output. Likewise, the /8 will correspond to every second pulse from the /4 output, and the /6 will correspond to every second pulse from the /3 output. Needless to say, the /2 and /3 groups are not related to each other, or to the /5 or /7 outputs. All however share a common external reset, so they can be synchronized. All outputs go high on reset.

Gated Comparator (Shifter)

I have used an 8 stage digital shift register as the memory element. Each clock pulse, the remembered level (logic 0 or logic 1) is moved into the next stage “bucket brigade” fashion, and the new value stored in the first memory cell. The result is a level (on or off) of the data input at the first output, plus time delayed versions of previous levels across the remaining outputs.

Quad Logic Gate

The Quad Logic Gate is a very simple module that can be built in one of six flavors : XOR, OR, AND, NOR, XNOR and NAND. It is a simple way to gain additional control of gate and trigger pulses within a system. It can also be used for some simple signal multiplying. The XOR is well known as a square wave “ring modulator”.


These are stripped down to essentials to fit into one Front-Panel-Express panel. It is the most dense of any of my modules behind the panel, with a total of eight PC boards. I added a divide-by-one output to the Pulse Divider as the output of the clock comparator. I omitted the “comparator out” of the gated comparator; it is a digital shifter. The Quad Logic Gate is built with XNOR gates, CD4077, which make a digital inverter using one input, a digital ring modulator with two inputs, and they convert any analog signal to a pulse train. All outputs are buffered by CGS-56 Gate Converters for +/-5V pulses (that took five CGS-56 boards).



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