Published on January 25, 2016
For more course tutorials visit www.uophelp.com 1. Define FM. 2. What parameter of the intelligence signal causes frequency deviation of the carrier? 3. What parameter of the intelligence signal causes or determines the rate of carrier frequency deviation? 4. Define modulation index for FM. 5. What is the reason that FM requires wider bandwidth as compared to AM? 6. What characteristics of FM signal are shown by Bessel Function Solution of FM signal? 7. If you are tuned to an FM station at a frequency of 100.1 MHz, show the bandwidth allocation for two adjacent stations. 8. What is the required BW to transmit an FM signal if the maximum deviation is 60 KHz and intelligence frequency is 15 KHz? 9. Determine the power distribution in carrier and sidebands if the transmitted power is 1,000 W and mf = 1 10. Why is Preemphasis required? 11. What is the RC time constant required for Preemphasis circuits? 12. An FM transmitter delivers to a 75 ohm antenna a signal voltage of V(t) = 1000 sin ( 109t + 4 sin 104t ) Determine: 13. Why are RF amplifiers necessary in FM receivers? 14. What are the two functions of a Limiter? 15. What is the meaning of the term center frequency in reference to FM broadcast? 16. What frequency swing is defined as 100 % modulation for an FM broadcast station? 17. Draw a block diagram for a Crossby FM transmitter for a transmitter frequency of 100.1 MHz. 18. The given diagram shows an FM transmitter. (a) What is the total multiplication factor? (b) What is the carrier rest frequency at the antenna? (c) What is the deviation of the radiated signal? (d) What is the % of modulation? (e) What is the modulation index? (f) How many sideband pairs are in the radiated signal? (g) What is the bandwidth of the radiated signal? (h) What is the input power to the final power amplifier? (i) What is the output power? (j) How much power is in the carrier? (k) How much total power is in the sidebands? (l) If not already at 100 % modulation, what level of input signal would cause 100 % modulation?