This circuit, obtained from old documentation, doubles the frequency of the pulses applied to the input. The circuit must be powered by a voltage of 5 V.
This traditional signal injector from a 1970s publication uses germanium transistors. We can mount it...
The basis of this circuit is an LM380 that drives a speaker that emits sound when moisture is...
This 3-channel transmitter for amateur analog TV from 902 to 908 MHz was found in a QST magazine...