Back before cell phones … before video games … before television … even before electric radios, there were crystal radio receivers. In the early 1920s and 1930s, magazines offered instructions on how ...

No nameplate or maker's marking. A fixed inductance coil with sliding control and crystal detector. Inductance of the tuning coil is varied by a slider. Binding posts on wooden base. A .0003 mfd.

Although GRC (the GNU Radio Companion) uses the word radio, it is really a graphical tool for building DSP applications. In the last post, I showed you how you could experiment with it just by using a ...

The AM broadcast band doesn’t have a lot of mainstream programming on it across much of the United States today. That’s a shame because a lot of kids got their first taste of radio and electronics by ...

Marked: "Martian / Big Four / Newark, New Jersey / Pat. Pend.". A crystal radio detector with binding posts for headphone connections on top, posts for antenna and ground connections on bottom.

A simple radio receiver used in the early days of radio. Comments are closed for this object What's this? Most of the content on A History of the World is created by the contributors, who are the ...