Found in a 1966 documentation, this “coin finder” uses components from the era operating at 2.1 MHz. The circuit uses an audio amplifier for detection.
The circuit presented is a 10 MHz oscillator with crystal, which already has several splitters for...
We found this circuit in the August 1994 Electronics Now magazine. The circuit is based on the...
This circuit was obtained in a 1982 Maplin magazine. The circuit can be applied to equivalent power...