List of top Physics Questions on communication systems asked in TS EAMCET

If the maximum and minimum amplitudes of an amplitude modulated wave are 9 V and 3 V respectively, then the modulation index is

If the frequencies of the carrier wave and message signal are $1$ MHz and $28$ kHz respectively, then the frequencies of the side bands are

The layer of the atmosphere which efficiently reflects high frequency waves particularly at night is

When the receiving antenna is on the ground, the range of a transmitting antenna of height 980 m is (Radius of the earth = 6400 km)