[sdiy] Notch Filter for Logon's Human-Capacitor Filter

[Mike I]

Only half-kidding... a  60 Hz + harmonics notch filter capable of  tracking
minor variations in line freq would make a good project in and of itself,
whether BBD/switched cap/DSP or some other technology is utilized   :D

And heck, my opinion of  OTAs is about the same as Harry's opinion of
BBDs... both can be very ornery devices to use when good performance is
required.
Cheers, M.



----- Original Message -----
From: Aaron Lanterman <lanterma at ece.gatech.edu>
To: Mike I <mirwin at marketbridge.ca>
Cc: <synth-diy at dropmix.xs4all.nl>
Sent: Thursday, December 14, 2006 11:52 AM
Subject: Re: [sdiy] Notch Filter for Logon's Human-Capacitor Filter


>
> On Thu, 14 Dec 2006, Mike I wrote:
>
> > Hey - use a BBD as a fixed comb filter to notch out 60 Hz and it's
> > harmonics - clock the BBD with a freq multiplier (PLL ?) that uses the
> > actual 60 Hz line freq as an input ,  so the notches track despite any
minor
> > deviations from 60 Hz.
>
> Logon - just to avoid confusing the poor students, I should mention Mike
> is just playin' with ya.
>
> Ask Harry Bissel what he thinks of BBDs.
>
> Harry, you will be happy to know that no BBDs ever came up at any time in
> my lectures. ;)
>
> - Aaron
>
> --------------------------------------------------------------------------
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