Adjustable Notch Filter circuit

Adjustable Notch Filter 38 to 86 Hz Circuit - Passive

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Hall Passive Notch filter circuit - offshoot
passive notch filter circuit analysis
passive notch filter circuit analysis - 2
A highly unique offshoot of the Hall Passive Notch filter that provides an adjustable - deep notch between 38 Hz and 86 Hz. Both R1 and R2 are tracked equal. At the 38 Hz notch, shown on the left - both pots are at 100 % of their shown values with a suppressed value of -37.5 DB.
With both pots at their “0” % position, shown on the right, the notch is -54.7 DB at 86Hz. In the left hand image the pass band is 300 to 10 KHz flat. The Right 1.5 to 10 KHz. The output must be fed into a minimum 50K  Load. Low frequencies below the notch values are also suppressed.