[sdiy] small VCO core (was Temperature stable lin-exp converter with a CA3086 or CA3046)

[jorgen.bergfors at idg.se]

> It would be nice to have a core VCO design. Just an
> expo convertor and a sawtoth oscillator.

Why sawtooth? My recent experiments show that it is much easier to shape
other waveforms from a triangle core.
Also, a triangle VCO doesn't have the problem with the sawtooth reset time.
Mine stays in tune to over 20kHz, without any HF compensation whatsoever.

/Jorgen