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( Common to Electronics & Communication Engineering and Electronics & Telematics)
(b) An AM amplifier provides an output of 106 W at 100% modulation. The internal loss is 20 W
i. What is un-modulated carrier power?
ii. What is the side band power? [10+6]
(b) When the modulation percentage is 75, an AM transmitter produces 10 KW.How much of this is carrier power? What would be the percentage of power saving if the carrier is suppressed before transmission took place. [8+8]
(b) A 400Wcarrier is modulated on depth of 75 percent; calculate the total power in the modulated wave in the following forms of AM:
iii. J3E. [8+8]
(b) FM is called a ‘Constant Band Width’ system-Justify with suitable illustrations.
(c) In a FM system if modulation index is doubled by halving modulating frequency, what will be the effect on the maximum deviation? [6+6+4]
(b) Explain about radio broadcast transmitters with the help of block diagram.7. (a) Describe the circuit of an FET amplitude limiter, and with the aid of the transfer characteristic explain the operation of the circuit.
(b) What can be done to improve the overall limiting performance of an FM receiver ? Explain the operation of the double limiter and also AGC in addition to a limier. 
(b) Explain clearly the generation and demodulation of PWM with the help of necessary diagram.