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.
The frequency of the signal produced by this oscillator depends on the amount of light falling...
The circuit presented is based on a mechanical tuning fork. The circuit is suggested by National...
This is a well-known RC oscillator configuration using a 741 operational amplifier. The circuit is from...