This audio-driven relay was published in the July 1977 issue of Radio Electronics magazine. The circuit uses CMOS components, and the relay must be a sensitive type.
With the coded activation of the relays, it is possible to control which of the 16 outputs...
The integrated circuit used in this application is not very common. Transistors and resistors...
This simple circuit makes use of neon lamps to indicate the voltage of a power grid. The lamps are...