If you have a 600 volts power supply lying around (perhaps from an old television), you can loan it to Junior, who will love making this science fair project. It uses lethal voltages, it lights up, and it makes noise! He or she will love it, and it’s bound to take home the blue ribbon.

The project appeared 60 years ago this month in the August 1964 issue of Popular Electronics. It is simplicity itself–you simply apply a high voltage to the fluorescent tube, and it lights up. But past a certain voltage, the current decreases with an increase in voltage, meaning that the resistance is negative. This phenomenon can be used to put the device into oscillation, and sound comes out of the headphones. The device can be used as a code practice oscillator, or simply to wow the judges at the science fair.