I'm playing with an idea for a VCO (Voltage Controlled Oscillator), and would like to make something a bit out of the ordinary. My idea is to run multiple sawtooth oscillators from a single control voltage, with the possibility of de-tuning the frequency of each individual Oscillator core to some degree.
I was hoping to make this quite simple, and was thinking of using a 40106 Hex Inverting Schmitt trigger for the oscillator cores, and a Voltage controlled Current Sink as the control for this (oscillator schematic in picture, where the sawtooth waveform is taken from the Schmidt trigger input).
Making a single such oscillator was not hard. However, once I want to combine 2 or more of these cores, I cannot figure out a reasonably simple way to share the current sink between them. As I would like to be able to slightly tune their individual frequency, just connecting them directly causes them to sync up to the fastest one.
I could of course create one Current Sink for each, but the circuit for this is quite complex and also temperature dependent. So it would be a lot simpler if I could share one sink for all cores.
Does anyone have any good suggestions? I am aware that this may be trivial (or impossible), but I am sadly not that fluent in electronics (especially analog circuits).