XR2207 and XR2209 VCO chips

[Jim Patchell]

    I tried to use these a long time ago (1977), and they are just not very
linear.  Frequency vs. Control Current is very bumpy, making the musically not
useful.  They are OK so long as you are not going to use them for a pitch
source.

    Jim

McIntosh, Malcolm wrote:

> Ok all,
>
> Can you tell me why the XR2207 or XR2209 VCO chip can not be used easily as
> a basis for a VCO?  I looked at the data specs and it says the have a sweep
> range of 1000:1, minimum.  Wouldn't that just cover the range of human
> hearing (20Hz to 20KHz)?  Lowest frequency 0.01Hz - Highest frequency 1MHz.
>
> Links:
>
> http://www.exar.com/products/xr2207.html
> http://www.exar.com/products/xr2209.html
>
> Malcolm