This circuit uses an MW radio tuned to around 540 kHz to detect atmospheric signals, for example, from an approaching storm. The circuit was taken from a Popular Electronics from the 90s.
This small transmitter can send its signals to a receiver placed at distances up to 100 m. The...
This transistorized siren was found in Popular Electronics from April 1967. The signal must be...
We show only one of the channels of an excellent audio preamplifier with the LM382 integrated...