Found in an Electronics World of 1969, this circuit causes a light bulb to flash along with the audio signal applied to the input. The circuit only works with incandescent lamps. C can be 47 nF to 220 nF.
This ohmmeter can be made with a scrap milliammeter used for continuity tests or even resistance...
This circuit was found in the November 1992 issue of Radio Electronics magazine. The circuit has...
Found in an English Maplin documentation from 1983, this circuit generates separate frequency...