Question

In the radio receiver, the device that separates AF signal from RF signal is_________.

Answer 1

Hint- AF signal is the signal which will convert into sound that you can hear by your eyes. RF is the carrier waves which carry audio. It is also known as radio frequency. Demodulator is the process of regaining information from carried waves, that is RF waves, at the receiver by separating AF.

Step by step solution:

We know that RF is the radio frequency whose range is in megahertz and above. It acts as a carrier wave in the communication field. AF is known as audio frequency whose range is between 20Hz to 20000Hz.
Before demodulation we have modulation. About demodulation, we will see later. First let’s see what modulation is.
The process of superimposing low-frequency signals on a high-frequency wave which acts as a carrier wave for long-distance transmission is known as a modulation.
In the radio transmitter, a device is needed which will combine the AF signal with the RF carrier wave signal before it is sent to the antenna. This is the function of a modulator, it combines the AF and RF signal so that information can be transmitted. The output of the modulator is called modulator RF.
The signal produced by the antenna in a receiver will be modulated RF.
In order to hear the voice as an output of the receiver, the AF component must be separated out. The demodulator removes the RF component of the modulator RF signal and produces an AF output. When the AF and RF signals are combined in the modulator, they must have the proper relative strengths for maximum efficiency.
The device that separates AF signal from RF signal at the receiver end is termed as a demodulator.

Note: The amount of modulation is called modulation rate. Demodulation is also known as the reverse process of modulation. AF and RF amplifiers are also. Do not get confused between AF and RF signals and AF and RF amplifiers. AF amplifier amplifies the amplitude of the wave that the listener amplifier amplifies amplitude of radio frequency waves.