1222 Tuner VCO Module

[Dud]

I’ve done it on several of my VCO, here’s the schematic part to add the octave switch selecter

3340 VCO Schematic for PCB design

Personally I would also suggest adding the octave selection, really very practical On my VCOs that don’t have it I miss it a lot [schematic2] [schematic3] R42 must be changed, i don’t remember exactely maybe 2K (i ll searched and come back ) EDIT : I found it, between 1K and 4.7K (By the way, R42 shown there is specified as 220 ohms but it really should be higher; 220R results in too much current through the voltage reference U4, potentially causing bad behavior and possi…