linear FM : was RE: [sdiy] Temperature Compensated VCO attempt - help?

[Czech Martin]

>That was what I was thinking about. Now, I'm sure you can invent all kinds of
>ingenous devices to go around it, and people do. You can go on forever. It's a
>endless story and among the major problems is to find the "optimum" balance
>between complexity and relative determism.

well , there are other limitations, too. We should not forget these.
It is carrier / modulator tracking, for example.
In the case that you just want to add some HARMONICS
andif the hardware will not meet some accuracy, severe beating 
of the fm partials may come up. This does not sound like the usual
oscillator phasing, but somehow wobbly.
If the modulator/carrier ratio is high, such problems
will be aggravated. 

I still wonder if this "Linear FM" feature is just for some
bellish sound effect, or if it works so good in existing
hardware that several octaves of tones can be played with
reasonable beating

In one case it is a "nice to have", in the later I would
consider it as "must have".

Or translated: relaxation oscillator simplicity
or triangle oscillator complexity (but with more fun).


Could some people who have actually built such linear FM
things please shed some light on that tracking issue?


m.c.


p.s.: I really would like to have some time for the experiments
I wanted to do. But at the moment I must finish this huge bird
cage I built with my wife. Situs undulatus needs a bigger home.
But of course this was not completely way off: somehow the
frame is similar to what I need for my modular,
coincidence? ;->
So I could gain some experience with wood working of such a frame.

If this thing is done I want to try all the dual transistors
I have, termo chamber and integrator for expo 
current output measurement. I want to separte effects from the
expo source from other effects. Just an excercise or education.

m.c.