Stroh Modular Dual Mirror Core VCO

A true beast of a dual osc to serve as the core of any MOTM system. 

The  3 PCB Set consists of two main OSC PCBs and a Control PCB. 

Included in the kit is the panel, 3 pcb set, all pcb components including the SMT voltage shunt, pots, switches, jacks etc.

This is a moderate to advanced build. there are ~450 pcb components including one SMT part. The build guide will walk through assembly step by step.

The module, as described by the designer, Dustin Stroh:

“The VCOs I'm calling "Mirror Core". It's our take on the internals of a CD4046 VCO, only built out using separate components. The CD4046 VCO didn't have high linearity for tracking in mind, so we've improved this significantly. I call it Mirror Core because it uses two opposing sawtooth cores, which is able to generate a perfect 50% square wave. 

One of the more unique features is that we expose a logic level unipolar output, which can be used for clocking and logic purposes. 

Features of the VCO: 

Coarse/Fine tune controls. 
1V/Oct input (high tracking range) 
Linear FM input 
PWM control 
PWM CV input 
VCO/LFO switch 

Saw wave out 
Tri wave out 
Sqr 50% wave out 
PWM wave out 
Logic pulse out 
Sine wave out 

VCA in 
VCA out 
VCA CV in 

Lockhart folder in 
Lockhart folder out 


Control Board Features: 

XOR A in + LED 
XOR B in + LED 
XOR out + LED 

Dual Edge Divide by N and Divide by N.5 in 
Dual Edge Divide by N and Divide by N.5 out 
Dual Edge Divider 16 position rotary 
Dual Edge Divider Edge Select switch 
Dividided signal LED 

LED driver 1 for VCO 1 Logic Pulse Out 
LED driver 2 for VCO 2 Logic Pulse Out 

Integrator in 
Integrator out 
Integrator Range control