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 circuit has very high input impedance and a differential input. The gain is 1,000 and the...
This circuit is more elaborate than the previous one. It was obtained from an 80s circuit manual. The...
This simple circuit for an audio link uses a lamp, which has a very poor frequency response, but...