MOTM-480 3u Dual Filters

The MOTM-480 CS-80 Resonant Filter consists of two identical state-variable Voltage Controlled Filters. Each filter circuit features: 1V/Octave frequency control input FM input with reversible attenuator VC resonance input High … Read More


I decided to build a VCO using Ken Stone’s CGS48 PC board. My version is minimal; it omits the additional waveshapers that are on the board. I was interested in … Read More

Mixer-Comparator DIY Module

UPDATED FOR 2006 This 1U-wide MOTM-format utility module combines a two-input mixer with an inverter and a comparator to create a versatile signal processor. I’ll describe the circuits first, and … Read More

MOTM-120R Sub-Octave Multiplexer

From the Synthtech website: The MOTM-120 is based on an article in Electronotes, updated with improved and added features. The MOTM-120 contains two four-stage sub-octave dividers, a digital multiplexer, and … Read More

Wiard Wogglebug

This is a special DIY module, based on the #3 Standard WoggleBug Circuit schematics given by Grant Richter on his website, together with the block diagrams of the Wogglebug on … Read More