it's ALIVE! (and v/hz vs v/oct question)

[Harry Bissell]

What you need is an logarithmic converter. The V/Hz already has an exponential
scale, so to make it linear, you need to take the log...

Bad news it will be temperature sensitive... needs stabilization or
compensation...
you will go from expo to linear (log) and linear to expo (antilog) in two
different places...
Maybe the midi converter (V/oct) is easier...

See also National Semiconductor App note AN-311 Theory and Applications of
Logarithmic Amplifiers for the "how to do it"

H^)

Michael Moncur wrote:

> Thanks again to everyone who answered my questions. I finished the FatMan
> yesterday, and it WORKS! Amazing. Actually I had one minor problem, one pin
> on an IC that I neglected to solder, but I only spent about two minutes
> troubleshooting.
>
> I'm having lots of fun playing with it. Granted, I have hardware and
> software synths that can do more, but this one's neat because I built it.
>
> Now, one question. I know the FatMan's CV output is the weird V/hz variety.
> Is there any quick and dirty way to convert this output to 1v/oct? I'm
> going to build a few homebrew things and would like to have a CV to drive
> them. If there's no easy way to do that, I guess I'll build a Midi2CV8 next...
>
> --
> michael moncur   mgm at starlingtech.com   http://www.starlingtech.com/
> "It is better to have loved and lost than never to have lost at all."
>                  -- Samuel Butler