Radio experimenters often need a variable capacitor to tune their circuits, as the saying goes, for maximum smoke. In decades past these were readily available from almost any scrap radio, but the ...

Sometimes when you need a component, the best way to get it is by building it yourself. [North Carolina Prepper] did just that, creating his own trombone-style variable capacitor by stretching 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 ...