This circuit is from a 2004 documentation serving for signals from 1 MHz to 160 MHz. The antenna is of the telescopic type and the analog instrument is of the type found in old sound equipment.
This alarm uses several sensors that directly trigger a sensitive relay. A larger relay can be...
This circuit for counting down pulses was found in the September 1983 issue of Radio Electronics...
Indicated by Popular Electronics to be used with a car headlight, this circuit can also have...