Suggested by a 90s Popular Electronics this circuit is intended to receive volleys or whistles from thunderstorms in the wave range below 20 kHz. The coil consists of 300 turns of wire 26 in a ferrite rod.
This high-gain circuit uses junction FETs (JFETs) and must be powered by somewhat high voltages. The...
The operational amplifier of this circuit is not very common today, because we removed the circuit...
This circuit was found in a 1973 magazine but can still be assembled using modern equivalent...