A crystal radio is basically a high Q resonator tied to an antenna and an envelope detector. These days the envelope detector is a point contact diode such as a 1N34 Germanium diode. The resonant ...

A staple of starting off in electronics ion years past was the crystal set radio, an extremely simple AM radio receiver with little more than a tuned circuit and a point contact diode as its ...

This fun little DIY device is labeled as a “crystal radio circuit in a jam-jar.” But that description doesn’t even to begin to do it justice. According to Tesla, this electronic wonder allows you to ...

A crystal radio set is almost like magic. Sound appears, seemingly out of nowhere, powered not by cords and batteries, but by the very air around you. “You can’t quite work out how it comes alive,” ...

The transmitter on 2 meters 144 MHz was designed mainly for use by radio amateurs as radio beacon and to this end, it produces a signal of good quality and without unwanted harmonics. T1 transistor, ...