Advertisements
Advertisements
प्रश्न
In the given block diagram of a receiver, identify the boxes labeled as X and Y and write their functions.
उत्तर
X → If stage → Intermediate frequency stage to change the carrier frequency to lower frequency.
Y → Amplifier → It amplifies the signal i.e. it increase the amplitude of the detected signal to compensate the attenuation of the signal. The detected signal may not be strong enough to use.
संबंधित प्रश्न
The carrier wave is given by
C(t) = 2sin(8πt) volt.
The modulating signal is a square wave as shown. Find modulation index.
A carrier wave of peak voltage 12 V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation index of 75%?
What is the role of a bandpass filter?
State any two types of modulation
The carrier wave of a signal is given by C(t) = 3 sin (8πt) volt. The modulating signal is a square wave as shown. Find its modulation index.
In the block diagram of a simple modulator for obtaining an AM signal, shown in the figure, identify the boxes A and B. Write their function.
A 20 volt AC is applied to a circuit consisting of a resistance and a coil with negligible resistance. If the voltage across the resistance is 12 volt, the voltage across the coil is ______.
Broadcasting antennas are generally ______.
I-V characteristics of four devices are shown in Figures.
![]() |
![]() |
![]() |
|
(i) | (ii) | (iii) | (iv) |
Identify devices that can be used for modulation.
A carrier wave Vc(t) = 160 sin(2π × 106t) volts is made to vary between Vmax = 200 V and Vmin = 120 V by a message signal Vm(t) = Am sin(2π × 103t) volts. The peak voltage Am of the modulating signal is ______.