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.
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...