[sdiy] expo accuracy? or integrator accuracy?, or both?

[René Schmitz]

Hi Scott,

>Wow.  Well, if I follow the thread correctly, René, you've done this! (and I
>built [and use] a copy of the circuit).  You put together a very simple VCO
>using a 4069 gate for an integrator.  For what it's worth in this discussion,
>I got 9 octaves of linear operation out of such a "poor integrator".  It seems
>that even a poor integrator is sufficiently accurate for musical use.  For me,
>it casts doubt on whether the other much smaller influences are worth
>investigating at all.

Well, that is true of course. And I know that the CMOS integrator can perform 
over more octaves than that. (I have tried variations of that circuit too.) 
The question here is not that of sweep range but of possible thermal effects. 
I'd say by learning how the integrator performs at a lower loop gain one can 
make a projection whether thermal (or other) dependancies of loop gain will 
have an influence on oscillator behaviour or not. 

Cheers,
 René


-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159