The transistors of this circuit may be the BC548 or BC549 and its power supply can be performed with voltages from 15 to 22 V. The circuit has a gain determined by the values of the components in the feedback circuit. The input connections and signal output should be shielded. Consumption is very low, on the order of a few milliamperes. If a power supply is used, it must have excellent filtration. The level of the output signal is of the order of a few hundred millivolts, enough to excite the input of most audio amplifiers. Input is average impedance. C has values between 4n7 and 47 nF.


 

 

 

GAIN 10 20 30 40 DB
R1 4k7 1,5 k 1,5 k 1 k Ω
R2 12 15 56 180
R3 470 560 330 680 Ω
R4 1,8 2,2 2,2 2,2
R5 1,2 k 470 270 220 Ω

Datasheets


N° of component