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1. Why would the power supply to an oscillator stage be regulated?

a) To provide maximum power output from the oscillator
b) To prevent the oscillator from producing a distorted sine wave
c) To prevent the oscillator from being "pulled" off frequency
d) None of the above

2. Where would one expect to find an RF bypass capacitor connected within a radio transmitter?

a) Between the final PA stage and the antenna
b) Between the oscillator and buffer amplifier
c) Between a power supply line and ground
d) None of the above

3. The oscillator in a certain transmitter produces 1 mW of output. The signal is subsequently amplified in the following stages:

Buffer: +10 dB
Modulator: +6 dB
Driver: +10 dB
Final: +13 dB

What is the final output power of this transmitter in Watts?

a) 8 Watts
b) 4 Watts
c) 400 mW
d) None of these

4. The oscillator in a certain transmitter produces +6 dBm of output. The signal is subsequently amplified in the following stages:

Buffer: +10 dB
Modulator: +6 dB
Driver: +10 dB
Final: +14 dB
Antenna Coupler: -1 dB
What is the final output power of this transmitter in Watts?

a) 8 Watts
b) 32 Watts
c) 400 mW
d) None of these

5. Where does the modulation take place at in a high-level transmitter?

a) At the oscillator
b) At the final power amplifier
c) At the buffer amplifier
d) Before the final power amplifier

6. What is meant by the term "dead-keyed?"

a) The unmodulated condition; 0% modulation
b) 50% modulated
c) 100% modulated; maximum output power
d) None of the above

7. What is the function of an RF bypass capacitor?

a) To couple signal from one stage to the next
b) To couple RF energy into the antenna
c) To force RF energy to go to ground
d) None of the above

8. What class of amplifier would be serve as a modulator?

a) Class A
b) Class B
c) Class C
d) None of the above

9. Which of these devices would provide the most stable oscillation frequency?

a) An RC time-constant
b) An LC resonant circuit
c) A quartz crystal
d) A ceramic resonator

10. What type of oscillator is pictured above?

a) Colpitts
b) Hartley
c) Armstrong
d) Pierce
e) None of the above

11. What type of oscillator is pictured above?

a) Colpitts
b) Hartley
c) Armstrong
d) Pierce
e) None of the above

12. What type of oscillator is pictured above?

a) Colpitts
b) Hartley
c) Armstrong
d) Pierce
e) None of the above

13. A certain crystal has the following characteristics: Ls=1 H, Cs=.001 pF, Rs = 150 Ohms, Cm = 5 pF. What is the parallel-resonant frequency of the unit?

a) 5.032921 MHz
b) 4.986123 MHz
c) 5.033424 MHz
d) None of the above

14. Another name for the parallel-resonant frequency of a crystal is the:

a) Pole
b) Zero
c) Maximum
d) Minimum

15. A certain crystal has the following characteristics: Ls=1 H, Cs=.001 pF, Rs = 150 Ohms, Cm = 5 pF. What is the series-resonant frequency of the unit?

a) 5.032921 MHz
b) 4.986123 MHz
c) 5.033424 MHz
d) None of the above

16. Another name for the series-resonant frequency of a crystal is the:

a) Pole
b) Zero
c) Maximum
d) Minimum

17. Which of the following specifies the most sensitive receiver? All the units have the same bandwidth. Hint: Convert all into absolute power units.

a) 1 uV into 75 Ohms for better than 10 dB S/N ratio
b) 0.5 uV into 50 Ohms for better than 10 dB S/N ratio
c) -120 dBm for better than 10 dB S/N ratio
d) -110 dBm for better than 10 dB S/N ratio

18. The two signal components that are produced in a diode-type AM detector circuit are:

a) The upper and lower sidebands
b) A DC level and the AC information signal
c) The carrier frequency and sidebands
d) None of these

19. A mixer is producing the following frequency outputs: 710 KHz, 455 KHz, 1165 KHz, 1875 KHz. What are the two most likely frequencies being applied?

a) 710 KHz, 1165 KHz
b) 1875 KHz, 1165 KHz
c) 1000 KHz, 875 KHz
d) 262.5 KHz, 300 KHz
e) None of these

20. The purpose of the frequency converter section of a superhet receiver is to:

a) Keep the output level at the speaker constant, regardless of input signal level changes
b) Eliminate the image response
c) Prevent local oscillator frequency drift
d) None of these

21. What section of a superheterodyne receiver is responsible for attenuation of the image frequency?

a) Detector
b) Preselector
c) Local Oscillator
d) None of these

22. What section of a superheterodyne receiver determines the receiver's bandwidth and selectivity?

a) Preselector
b) IF Amplifier
c) Detector
d) Audio Amplifier
e) None of the above

23. What is the first step that must take place in receiving a radio signal?

a) Select (Tune desired carrier frequency)
b) Demodulate (Detect)
c) Amplify RF Signal
d) Acquire an RF signal

24. Why can't TRF receivers be constructed for high-frequency (above 1-2 MHz) use?

a) Insufficent "Q" is available from discrete LC components at these frequencies
b) Transistors and ICs have insufficient gain at these frequencies
c) Detector circuits produce excessive distortion at these frequencies
d) None of the above

25. Another name for demodulation is:

a) Selection
b) Acquisition
c) Detection
d) None of these

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