In a line of sight radio communication,a distance of about $50\, km$ is kept between the transmitting and receiving antennas. If the height of the receiving antenna is $70\, m$,then the minimum height of the transmitting antenna should be........$m$ (Radius of the Earth $= 6.4 \times 10^6\, m$)

The total power content of an $AM$ wave is $1500 \, W$. For $100 \%$ modulation,the power transmitted by the carrier is ........ $W$.

If the highest modulating frequency of the wave is $5\, kHz$,the number of stations that can be accommodated in a $150\, kHz$ bandwidth are

Which frequency range is allocated for commercial $FM$ radio broadcasting?

The modulation frequency of an $AM$ radio station is $250\, kHz$,which is $10\%$ of the carrier wave. If another $AM$ station approaches you for license,what broadcast frequency will you allot? (Note: The interval between two carrier frequencies should be at least two times the modulation frequency to avoid interference.)

The transmission of $UHF$ range frequencies is done by.........