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7-1. Define angle modulation.

7-2. Define direct FM and indirect FM.

7-3. Define direct PM and indirect PM.

7-4. Define frequency deviation and phase deviation.

7-5. Define instantaneous phase, instantaneous phase deviation, instantaneous frequency, and

instantaneous phase deviation.

7-6. Define deviation sensitivity for a frequency modulator and for a phase modulator.

7-7. Describe the relationship between the instantaneous carrier frequency and the modulating signal

for FM.

7-8. Describe the relationship between the instantaneous carrier phase and the modulating signal for

PM.

7-9. Describe the relationship between frequency deviation and the amplitude and frequency of the

modulating signal.

7-10. Define carrier swing.

7-11. Define modulation index for PM and for PM.

7-12. Describe the relationship between modulation index and the modulating signal for FM; for PM.

7-13. Define percent modulation for angle modulated-signals.

7-14. Describe the difference between a direct frequency modulator and a direct phase modulator.

7-15. How can a frequency modulated be converted to a phase modulator; a phase modulator to a

frequency modulator?

7-16. How many sets of sidebands are produced when a carrier is frequency modulated by a single input

frequency?

7-17. What are the requirements for a side frequency to be considered significant?

7-18. Define a low, a medium and a high modulation index.

7-19. Describe the significance of the Bessel table.

7-20. State Carsons general rule for determining the bandwidth for an angle-modulated wave.

7-21. Define deviation ratio.

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7-22. Describe the relationship between the power in the unmodulated carrier and the power in the

modulated wave for FM.

7-23. Describe the significance of the FM noise triangle.

7-24. What effect does limiting have on the composite FM waveform?

7-25. Define preemphasis and deemphasis.

7-26. Describe a preemphasis network; a deemphasis network.

7-27. Describe the basic operation of a varactor diode FM generator.

7-28. Describe the basic operation of a reactance FM generator.

7-29. Describe the basic operation of a linear integrated-circuit FM modulator.

7-30. Draw the block diagram for a Crosby direct FM transmitter and describe its operation.

7-31. What is the purpose of an AFC loop? Why is one required for the Crosby transmitter?

7-32. Draw the block diagram for a phase-locked-loop FM transmitter and describe its operation.

7-33. Draw the block diagram for an Armstrong indirect FM transmitter and describe its operation.

7-34. Compare FM to PM.