How do you use a variable capacitor?

Variable capacitors are often used in L/C circuits to set the resonance frequency, e.g. to tune a radio (therefore it is sometimes called a tuning capacitor or tuning condenser), or as a variable reactance, e.g. for impedance matching in antenna tuners.

Where the variable air capacitor is used?

Variable air capacitors are used in circumstances where the capacitance needs to be varied. They are sometimes used in resonant circuits, such as radio tuners, frequency mixers or antenna impedance matching applications. Another use for variable capacitors is while prototyping an electronic circuit design.

What is the working voltage of a variable capacitor?

Trimmer capacitors can be rated for voltages up to 300 volts, although voltage ratings of up to 100 volts are much more common. Since trim caps are variable capacitors, they come in a capacitance range rather than a single capacitance value.

How to build your own transmitting air variable capacitors?

For a 220pf capacitor of 12 plates, 4-1/2″ is adequate. Mount these in the back end plate, leaving 3/8″ to 1/2″ beyond the outside nut. Secure them to the inside using 2 nuts per rail to leave adequate space for the rotor. Begin mounting the stator plates. First flatten them as much as possible, removing the bows, twists, and curls.

How many plates are in an air variable capacitor?

You can experiment with the number of plates and with the size op gaps by adding more plates and washer, in the rotor and stator. On this step we will do the measurements.

How big is a Johnson Air variable capacitor?

Johnson air variable trimmer capacitor with coil attached with 3 turns. 1.8 – 8.7 pF @ 1250v. 9 plates. 3/16″ shaft. “LC” network. Nifty variable with built-in vernier ball drive. 2 kv plate spacing. 1/8″, 1/4″ shafts. Mounts by end plates. 1-3/8″ x 1-3/8″ x 1″ deep. Knob set $8.

What is the definition of a variable capacitor?

A capacitor whose capacitance can be varied based on the requirement to a certain range of values is defined as a Variable Capacitor. These types of capacitors consist of plates made of metals. Among these plates, one will be fixed while the other is movable.