If you enjoy building radio projects you may have noticed something slightly worrying over the last few years in your component supply. Variable capacitors are no longer as plentiful as they used to ...

[Jezan] decided to introduce his son to electronics by building a small crystal radio. These crystal sets have been around for a long time, and make for a great beginner electronics project, but some ...

How do you implement a variable capacitor these days? Mechanical caps are out. That leaves varactors, which work fine but require higher voltages that often are not available, and their response is ...

Marked: "JB" on top. An adjustable plunger set in a stand, moves within a glass cylinder into a metal cup at the bottom. Two contacts, one on top plate, the other on the base plate. This may be a ...