Pitch Extractor

[Harry Bissell]

At the risk of sounding (or actually being) ignorant...

Success will depend on the input frequency, and the amount of delay you can
stand.  Having 'borrowed' the JH frequency shifter values for research
purposes...
I did a spice simulation. The 90 degree phase shift is right on... but group
delay
(in the range I want... Guitar range = 80Hz) is pretty poor. It would be so
slow that
I could not use it for my application.

But in higher ranges... it might work fine.

sorry I have no favorite multiplier (that is still available...)

H^) harry

Scott Bernardi wrote:

> I'd like to include a pitch extractor in my new synth, and an article in
> ElectroNotes 136 on using a Hilbert transform to remove upper harmonics
> and emphasize the fundamental looks very interesting. The article was
> more of an experiment than an actual module built. My Electronotes
> subscription ran out soon after that issue (wish I had kept it up, now)
> - does one of you that have a full set know if Bernie pursued that
> subject in later issues? If so, I'd sure like to get my hands on a copy.
>
> The Hilbert transform is realized by a 90 degree phase delay network
> feeding a couple of multipliers hooked up as squarers.  What do people
> use for multipliers?  AD633's seem very hard to locate; Arrow
> Electronics has ICL8013's listed on their website. I'd like to use
> something more accurate than OTA's, but also don't want to spend over
> $10 per chip.
>
> --
> Scott Bernardi
> sbernardi at home.net