This circuit is from a Radio Electronics from March 1970. The crystal depends on the frequency at which the signal is to be captured and the resonant circuit determines the tuned band.
Vishay's VCNL4200 integrated circuit consists of a fully integrated proximity detector containing...
This circuit samples the current in a load and in case of excessive value it activates a...
The frequency of this oscillator depends on the crystal used and the transistors. The circuit was...