The slug tuned inductor is a variable inductor having an adjustable ferrite core. The value of inductance increases or decreases respectively, due to the movement of a ferrite core into or out of the coil winding.
Construction of slug tuned inductor:
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The basic construction of a slug tuned inductor is shown in above figure.
- The construction is similar to the fixed ferrite core inductors, except the core is adjustable.
- When the slug is moved into the coil winding the value of inductance increases and decreases the resonant frequency of the tuned circuit.
- When the slug is moved out of the coil winding, the inductance decrease and the resonant frequency of the tuned circuit increases.
- The value of inductance can be varied by using movable core which can be moved up or down by using screw driver.