Question

In T.V. broadcasting both picture and sound are transmitted simultaneously because :

• A. audio signal is frequency modulated and video signal is amplitude modulated
• B. both audio and video signals are frequency modulated
• C. audio signal is amplitude modulated and video signal is frequency modulated
• D. both audio and video signals are amplitude modulated

Answer 1

Answer: (A)

audio signal is frequency modulated and video signal is amplitude modulated

If both sound and picture signals are to be modulated on a single carrier wave(since they are transmitted simultaneously), one has to be frequency modulated and the other has to be amplitude modulated. Both the signals can't be modulated by the same method on the same carrier wave, otherwise the demodulation would be impossible.