Q7.10 A radio can tune over the frequency range of a portion of broadcast band: . If its circuit has an effective inductance of , what must be the range of its variable capacitor?
Range of the frequency in which radio can be tune =
The effective inductance of the Circuit =
Now, As we know,
where is tuning frequency.
For getting the range of the value of a capacitor, let's calculate the two values of the capacitor, one maximum, and one minimum.
first, let's calculate the minimum value of capacitance which is the case when tuning frequency = 800KHz.
Hence the minimum value of capacitance is 198pF.
Now, Let's calculate the maximum value of the capacitor.
in this case, tuning frequency = 1200KHz
Hence the maximum value of the capacitor is 88.04pf
Hence the Range of the values of the capacitor is .