Dr. Gerald N. Johnson, P.E. wrote:
>
> Its not true that a twin-tee notch filter in the feedback will cause
> greater reduction in the noise at the notch frequency. Quite the
> contrary, a twin-tee notch filter in the feedback makes a bandpass
> amplifier. At least 4 decades ago, maybe 6, General Radio based an audio
> spectrum analyzer (manual type) on a twin-tee feedback network and an
> amplifier.
>
> Oh, it takes three R and three C to make a twin tee network.
>
> 73, Jerry, K0CQ
Wouldn't it make a difference if the twin-tee was included in
degenerative vs a regenerative feedback. I would think it would make a
big difference. In the above context, what kind of feedback? Just
wondering??
73,
Jim WD4AIR (FAA Retired)
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