JFET Mike Preamp/Equalizer
Some typical Voltages are;
Battery 9 VDC
Drain 7.1 VDC
Source 1.8 VDC
Gate= near Zero
The 1 Mfd. Output Cap is non-polar. To RF proof the input I put a miniature 470 micro henry choke in series between the gate input and the 10-20 megohm resistor along with a 18 pf cap from gate to ground at JFET. All short leads please ! You may build the circuit without pots. Full bass boost would be up in the drain near +9 VDC the .1 across a fixed 10K Resistor, which is good feeding many transmitters. In most cases I would use a pot for treble/sibilance boost control running more boost when my signal was weak at the other end, less when strong.
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