This transistorized siren was found in the patent section of Radio Electronics magazine from March 1968. The circuit uses components from the time and has a very elaborate configuration.
The circuit shown is an AND gate with three inputs using a comparator of the four existing in an...
This circuit, which can only be used with incandescent lamps, is adapted to the common wall...
This passive circuit was found in the March 1995 issue of Elexctonics Now magazine. The circuit is for...