For a broadcast FM radio transmission, state: (i)carrier frequency range; (ii)local oscillator frequency range. (9 marks)June/July 2020

(i) Carrier frequency range: In a broadcast FM radio transmission, the carrier frequency is the frequency of the radio waves that are used to transmit the information. The carrier frequency range for FM radio transmission is 87.5 MHz to 108 MHz. This range is divided into 100 channels, each with a bandwidth of 200 kHz.

(ii) Local oscillator frequency range: In a radio receiver, the local oscillator generates a frequency that is mixed with the incoming radio signal to produce an intermediate frequency (IF). The frequency of the local oscillator is usually set to a fixed value that is slightly above or below the frequency of the incoming signal.

For FM radio reception, the local oscillator frequency range is typically set to a value that is 10.7 MHz above the carrier frequency. For example, if the carrier frequency is 87.5 MHz, the local oscillator frequency would be set to 98.2 MHz. This produces an IF of 10.7 MHz, which is the frequency that is used to demodulate the FM signal in the radio receiver.