Questions tagged [varicap]

Varicaps are electronic components with a variable capacitance. They are a type of diode that, when operated under reverse bias, vary the width of their depletion zone and therefore their capacitance.

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Can two diodes be parallelled in RB to get double the capacitance?

It's a fact of life that air-gang capacitors, are increasingly more difficult to come by - having been superseded by the far more compact varactor diodes. My part of the world components such as the venerable BB212, MPN3700, MV1662 are almost…
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Does the varactor bias supply have to be independent of Vcc?

A quick follow-up to How can I tell the frequency without an oscilloscope, or frequency counter? My supply is a transformer plucked from a dead power adapter rated for 1.5A. This is rectified cap-filtered, then Vo manipulated through an LM317 with…
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How to generate FM narrowband using varactors

I don't really understand how FM narrow band is created, and at the same time I can't figure out how using this simple circuit of varactors (varicap diodes) we narrow the bandwidth. simulate this circuit – Schematic created using CircuitLab
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