This flashlight project with a blinking light that makes it easy to find was found in the January 1990 issue of Radio Electronics magazine. The light uses a common light bulb.
This is an old test circuit for integrated TTL counters, feeding a Nixie tube, common at the time....
This traditional crystal radio circuit, but which has a modern version with diode, was found in an...
This headphone amplifier using a pickup coil can be used as an extension for devices such as TVs,...