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1. What is the wavelength of a 600 MHz signal?

a) 1 Meter
b) 0.5 Meter (50 cm)
c) 0.75 Meter
d) None of the above

2. Why can't audio frequencies be directly transmitted through an antenna system?

a) The antenna required would be too long
b) Too much power would be required
c) The receiver would distort the information waveform
d) None of the above

3. In troubleshooting a stage in an electronic device, where is the best place to check the power supply?

a) At the output terminal of the voltage regulator IC
b) Directly at the terminals of the device using the power
c) At the power supply buss line
d) None of the above

4. What difference between radio stations allows receivers to separate them?

a) Each has a different amplitude
b) Each has a different phase
c) Each has a different frequency
d) None of the above

5. What type of filter is used to separate radio stations in a receiver?

a) Bandpass
b) Highpass
c) Lowpass
d) None of the above

6. A certain transmitter's antenna is 1/4 wavelength long and measures 29.528 inches. What is the actual operating frequency of this transmitter? (1 inch = 2.54 cm).

a) 25 MHz
b) 50 MHz
c) 100 MHz
d) None of the above

7. What is the wavelength of a 1 MHz signal?

a) 100 Meters
b) 200 Meters
c) 300 Meters
d) None of the above

8. Why is modulation and carrier transmission necessary in radio?

a) To keep antenna lengths reasonable
b) To allow stations to be separated by radio receivers
c) Both A and B
d) None of these

9. What is the frequency of the 3rd harmonic for the signal above?

a) 1 KHz
b) 2 KHz
c) 3 KHz
d) None of these

10. The signal shown above is fed into a bandpass filter with a center frequency of 2 KHz. What will the output of the bandpass filter look like on an oscilloscope?

a) A 1 KHz square wave
b) A 1 KHz sine wave
c) A 2 KHz triangle wave
d) None of the above

11. The signal shown above is fed into a bandpass filter with a center frequency of 1 KHz. What will the output of the bandpass filter look like on an oscilloscope?

a) A 1 KHz square wave
b) A 1 KHz sine wave
c) A 2 KHz triangle wave
d) None of the above

12. What laboratory instrument is used to view signals in the frequency domain?

a) Oscilloscope
b) Function generator
c) Spectrum analyzer
d) None of the above

13. What type of noise is produced by devices with forward-biased PN junctions?

a) Cosmic noise
b) Johnson noise
c) Thermal noise
d) None of the above

14. Which of these could be classified as an external noise source?

a) Shot Noise
b) Atmospheric noise
c) Flicker Noise
d) None of the above

15. Which type of noise is caused by the thermal agitation of charge carriers within a conductor?

a) Atmospheric noise
b) Cosmic noise
c) Johnson noise
d) None of the above

16. What signal to noise ratio, in dB, will result if a system has 1 mW of noise and 100 mW of signal power?

a) 10 dB
b) 20 dB
c) 30 dB
d) None of the above

17. What is the percentage of modulation of the AM signal pictured above?

a) 20%
b) 10%
c) 30%
d) None of the above

18. A certain AM transmitter produces 10W of power into a 50 Ohm load with no modulation. What total power will be produced at 100% modulation?

a) 15 W
b) 20 W
c) 30 W
d) None of the above

19. An AM signal was measured on an oscilloscope. The readings were Vmax=300 V, and Vmin = 150V. What is the percent modulation?

a) 33.3 %
b) 50 %
c) 75 %
d) None of the above

20. What is the information frequency in the AM signal pictured above?

a) 1 KHz
b) 2 KHz
c) 4 KHz
d) 5 KHz

21. An AM transmitter is operating on a carrier frequency (Fc) of 10.000 MHz, with 5000 volts of carrier (Vc). The transmitter is operating at 70% modulation. What is the voltage in the upper side band?

a) 3500 V
b) 2750 V
c) 2000 V
d) 1750 V

22. What is the total bandwidth of the AM signal pictured above?

a) 2 KHz
b) 700 KHz
c) 10 KHz
d) None of the above

23. What bandwidth will be required to transmit a 2 KHz sine-wave tone on an AM carrier wave if the carrier frequency is 118 MHz?

a) 10 KHz
b) 4 KHz
c) 8 KHz
d) None of these

24. What is the frequency of the upper sideband for an AM transmitter with a carrier frequency of 710 KHz and an information frequency of 5 KHz?

a) 710 KHz
b) 711 KHz
c) 712 KHz
d) None of the above

25. An AM signal was measured on an oscilloscope. The readings were Vmax=400 V, and Vmin = 100V. What is the percent modulation?

a) 33.3%
b) 60 %
c) 75 %
d) None of the above

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