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 ...

If you’ve seen a big air-variable capacitor, you may have noticed that some of the plates may have slots cut into them. Why? [Mr Carlson] has the answer in the video below. The short answer: you can ...

The inside of classic radios holds wonders that the sterile chips and SMD components of today’s circuits can’t hold a candle to. Chunky resistors and capacitors, vacuum tubes with cathodes aglow, and ...

The first British commercially available high-vacuum variable capacitors have been announced by the English Electric Valve Co. So 64 years ago, started a story in Electronics Weekly’s edition of March ...

For the PDF version of this article, click here. Click to read part I and part III of this article. In part one of this article (see “SPICE Analog Behavioral Modeling of Variable Passives,” March 2005 ...