Moon Modular M569
Quad Sequential Voltage Source

I purchased a Moon Modular M569 sequencer which is my first Moog/Dotcom format module.  I built new wood side cabinets which has one row for Dotcom format modules.




I use a MOTM-990 power distribution board and built a MOTM-to-Dotcom power cable.



I replaced the 16ESB T5 slide base lamp with a 28ESB (Mouser 606-CM28ESB) to decrease the brightness and covered it with a red plastic cover - much less obnoxious!




This is my first M569 sequence in 4x8 mode.  Channels 1-3 drive the Living VCO and channel 4 drives the 566 VCO modulated by noise through a resonant low pass gate which is modulated by a sequencer gate.




While I like this sequencer a lot, I really want to be able to slave other devices to it.  You can use the Shift inputs to slave it to an external clock but it would be nice to have the Clock and Run signals to drive other modules.  I took my unit apart and there is a separate PCB for the clock generation circuitry with a 14 pin interface.  I mapped out the pins and it would be easy to buffer these signals.

Connector top view - key to left


I made a new clock interconnect cable that brings these three signals and ground out to a MTA connector.


I designed a 1MU companion module to bring out buffered M569 Clock, Run, and Reset signals to jacks.  Moog Sequencer-style Start and Stop jacks and switches gate an external Clock In that can be used to drive the M569 Shift Inputs.  The Clock Out starts on the next rising edge following the Start and is stopped on the next falling edge following Stop so there are no truncated clocks.


I'm using a simple differentiator to debounce the switches and toggle a RS flip-flop to create a run signal.  The edges of Clock In are used to sample the run signal on so the clock gate only changes state when the Clock Out is low.  That ensures there are no truncated clocks although there  can be a lag since the clock will complete a full cycle before starting or stopping.

M569 Companion Schematic  unverified

This image shows the start pulse, differentiator output, input pulse and the output from the RS flip-flop.



Finishing Touches

I had 4 MU of panel space left in my cabinet so I made a blank panel from a piece of the rear panel.  It looked bare so I made a decal of the Moon Modular logo.  I finished the panel with two coats of polyurethane over the decal.