Introduction to tuned circuits
When a radio or television set is turned on,
many events take place within the "receiver" before we hear the sound
or see the picture being sent by the transmitting station. Many different
signals reach the antenna of a radio receiver at the same time. To select a
station, the listener adjusts the tuning dial on the radio receiver until the
desired station is heard. Within the radio or TV receiver, the actual
"selecting" of the desired signal and the rejecting of the unwanted
signals are accomplished by means of a tuned circuit.
A tuned circuit consists of a coil and a
capacitor connected in series or parallel. Whenever the characteristics of
inductance and capacitance are found in a tuned circuit, the phenomenon as
RESONANCE takes place.