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 oscillator with emitter follower was found in an American documentation from the 80's. The...
We found this circuit in 2005 Linear Technology documentation. The integrated circuit is LT1787...
The circuit is suggested by National Semiconductor in its 1994 Linear Applications Handbook. The...