3 In a standard AM broadcasting the total bandwidth of a bro

3. In a standard AM broadcasting, the total bandwidth of a broadcast station is _______ kHZ. A. 14 B. 2 C. 5 D. 10

4. The amount of modulation of a carrier is usually given as a modulation A. quantity. B. maximum. C. selection. D. percentage.

5. A 1,000 kHz RF carrier is amplitude-modulated by a 5,000 Hz sinewave signal. The upper sideband frequency would be A. 1,005.5 kHz. B. 995 kHz. C. 1,010 kHz. D. 1,005 kHz.

6. Some methods of pulse modulation provide for transmission of a number of channels on a single carrier. That is accomplished by dividing the transmission time among the several channels, which is called A. frequency-shift keying. B. duplexing. C. damping. D. multiplexing.

7. A 1,000 kHz carrier is amplitude-modulated by a 1,000 Hz sinewave audio signal. The lower sideband frequency would be A. 1,010 kHz. B. 999 kHz. C. 1,001 kHz. D. 989 kHz.

8. All receivers that are designed for suppressed carrier reception must be able to A. block any trace of a carrier. B. eliminate one sideband. C. reinsert a carrier frequency. D. reduce modulation phase shift.

9. A 1,200 kHz RF carrier is amplitude-modulated by a 500 Hz sinewave audio signal. The upper sideband frequency would be A. 1,205 kHz. B. 1,200.5 kHz. C. 120.5 kHz. D. 1,195 kHz.

10. Which of the following is used by a product detector? A. Amplitude limiting B. A ratio detector C. An oscillator for carrier reinsertion D. A special transformer

11. In a standard AM transmission with 100 percent modulation, A. the sideband amplitude is one-fourth of the carrier amplitude. B. the sideband amplitude is 50 percent of the carrier amplitude. C. the sideband amplitude is 70.7 percent of the carrier amplitude. D. the sideband amplitude is one-eighth of the carrier amplitude.

14. An unmodulated carrier has an amplitude of 10 V. When modulated, the maximum amplitude is 15 V. What\'s the modulation percentage? A. 120 percent B. 30 percent C. 100 percent D. 50 percent

15. An amplitude-modulated RF carrier is said to be _______ percent modulated when it rises to double its peak value on a modulation crest (or peak). A. 25 B. 50 C. 75 D. 100

16. In frequency modulation, the ratio of the maximum deviation (fD ) from the idling frequency to the audio modulating frequency (fA ) is called the A. maximum modulation. B. frequency ratio. C. sideband ratio. D. modulation index.

17. _______ modulation is particularly adaptable to computer systems, data transmission, and space communications. A. Pulse B. Pulse-amplistude C. Pulse-position D. Phase

18. In pulse-modulated systems, the interference caused by the operation of electronic switches is called A. damped waves B. envelope distortion. C. jitters. D. dead air.

19. In pulse-code modulation, numbers are used to represent the waveform\'s A. phase. B. frequency. C. time. D. amplitude.

20. In _______ modulation, the position or spacing of an intelligence pulse relative to a reference point is its principle of operation. A. pulse-position B. pulse-amplitude C. pulse-code D. phase

Solution

(1)

Option A is correct because the voltages magnitudes are different but phase shift is same so The input signal in this circuit is at resonance, and the discriminator\'s secondary voltages cancel each other.