Question

The RF channel in a radio transmitter produces:
(A) Audio signals
(B) High frequency carrier waves
(C) Both audio signal and high frequency carrier waves
(D) Low frequency carrier waves.

Answer 1

Hint: We can use the concept that a carrier wave is the continuous electromagnetic radiation, of constant amplitude and frequency, that is given out by a transmitter. The carrier wave is modulated in direct proportion to the signal, such as the voice or music, that is to be transmitted. The purpose of the carrier is usually either to transmit the information through space as an electromagnetic wave (as in radio communication), or to allow several carriers at different frequencies to share a common physical transmission medium by frequency division multiplexing (as in a cable television system).

Complete step by step answer
It is known that the RF channel is the channel that the TV station uses to broadcast its signal. Before the conversion to digital, TV stations were normally identified by their channel number, and most people knew that a particular network was on a specific TV channel. RF Antenna input is typically used to connect a television antenna, cable TV wire, or satellite feed to a television, VCR, or other device that can process radio-frequency video signals, including some computers.
We know that mixing up of signals from the transmitters operating in the same band necessitates frequency modulation because the signals get mixed and there is no simple way to distinguish between them. The RF channel in radio transmitters produces High frequency carrier waves as then signals cannot overlap and also the power losses are reduced.
So, the RF channel in a radio transmitter produces high frequency carrier waves.

Hence, the correct answer is option B.

Note: We can conclude that for the transmission of audio signals at distant places, the high frequency carrier waves are used, because these frequency carrier waves travel through space or medium with the speed of light and they are not obstructed by earth's atmosphere. To increase the energy of the signal we need to increase the frequency. This is when the carrier frequency is higher, and we noticed that bandwidth is just twice of the highest frequency of modulating signal. and the signal will be easily demodulated at the receiver end. Modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted.