$A$ telephone link operating at a central frequency of $10\, GHz$ is established. If $1\%$ of this is available,then how many telephone channels can be simultaneously provided,given that each telephone covers a bandwidth of $5\, kHz$?

The maximum and minimum amplitude of an amplitude modulated wave is $16\, V$ and $8\, V$ respectively. The modulation index for this amplitude modulated wave is $x \times 10^{-2}$. The value of $x$ is .........

In amplitude modulation,determine the total maximum transmitted power in $kW$,if the carrier output is $1 \, kW$.

In amplitude modulation,the message signal $V_{m}(t) = 10 \sin(2 \pi \times 10^{5} t) \text{ V}$ and the carrier signal $V_{c}(t) = 20 \sin(2 \pi \times 10^{7} t) \text{ V}$. The modulated signal contains the message signal with lower sideband and upper sideband frequencies. Therefore,the bandwidth of the modulated signal is $\alpha \text{ kHz}$. The value of $\alpha$ is:

Consider an optical communication system operating at $800 \, nm$. Suppose,only $1\%$ of the optical source frequency is the available channel bandwidth for optical communication. How many channels can be accommodated for transmitting audio signals requiring a bandwidth of $8 \, kHz$?

An optical fibre communication system works on a wavelength of $1.3 \mu m$. The number of subscribers it can feed if a channel requires $20 \ kHz$ is: