Q10 of 805 Page 1

Give reason, why high frequency carrier waves are needed for effective transmission of information signals.

OR


What is the range of frequencies used for T.V. transmission? State two factors by which the range of TV signals can be increased.

The main reason for using high frequency carrier waves for effective transmission of information signals is because it allows smaller antenna design.


Usually antenna length is given by L = wavelength/4


If carrier wave is not used, then for sending audio frequency of even 20 Hz, the antenna length would be


.


A high frequency carrier would significantly reduce the antenna length.


OR


Range of frequencies for TV transmission are 76-88 MHz and420-890 MHz.


The range of transmission of TV signals can be increased by


(1) Increasing the height of transmission tower.


(2) Using repeater stations.


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