Tuesday, 26 August 2025

"Moog" LFO, and Ribbon Controller PCB

 Two new offerings:

First, we have a simple triangle/square LFO module, inspired by those in Keith Emerson's custom Moog Modular - complete with "repurposed" 902 panel and "dymo" labels.

 -          Outputs:

o   Triangle: ± 3V

o   Square: ± 4V

-          Typical Frequency ranges:

o   Low range: 0.06 to 2.5 Hz

o   High range 0.2 to 17Hz

o   Use of the CV inputs will extend these up to approx 35Hz

 Range etc can be tailored by the builder. 

 (See "Moog eurorack module" page)

   

Secondly, a  basic analogue ribbon controller, originally designed to go with my Eurorack “moog” system. It is designed to use a Spectra Symbol linear “softpot”, with an optional Interlink electronics pressure sensor (FSR).

This is a PCB only offering (no panel) as it is designed to be built into a housing of your choice.

 Features:

-          Constant current ribbon drive (supports “hammer-ons”).

-          Position CV output

-          Gate (Moog “V-trigger”) output

-          Moog “S-trigger” output

-          Support for optional pressure sensor and pressure CV output

 ( (See "Utility PCBs" page)

 


 

 


Wednesday, 20 August 2025

992 to 904C

 I've updated the 904C build manual (V1-3) to include more info on connecting a 992 "Control Voltages" module to the 904A and 904B filters when a 904C is also connected . This now covers the Fitzgreyve 992, Behringer 992, and AMSynths AM992.

Tuesday, 17 June 2025

Free 100m-ish Analogue Delay panels

I've recently tried to get a colour match to the grey Behringer 100m panels. This has resulted in a lot of spare "100m-ish Analogue Delay" panels that are "not quite right". I'm giving these grey panels away free if your purchase an analogue  delay PCB - select "lighter" or "darker" but otherwise it's my choice. 

Tuesday, 18 February 2025

6401 Ring Modulator


The  6401 is a Eurorack implementation of the Moog Bode 6401 Ring Modulator.

The core ring modulator circuit is passive, using diodes and transformers.

The balanced output circuit has been replaced by a CP3 mixer circuit, which also enables the input signals to be mixed with  the modulator output.

 Build options:

-          The full circuit

-          Omit the squelch (noise gate) circuit

-           As a “passive” ring modulator only

Due to the small size of Eurorack modules, it is not possible to accommodate the originally specified transformers (even if you could find them!).

A choice of two types of transformers is supported depending on available budget: Edcor (as pictured), or Xicon (limited bandwidth).

The build is not difficult, but if the squelch circuit is included, component placement on the main PCB is dense to fit everything in, so accurate soldering is required.

If anyone wants to do a build using Xicon transformers,  I'll supply a free set of PCBs in return for photos of the build.

Depth behind the panel is approx. 40mm, this is heavy - 8oz / 250g.