Practice Exam

E6C02

1. What happens when the level of a comparator's input signal crosses the threshold voltage?

• A. The feedback loop becomes unstable
• B. The reference level appears at the output
• C. The IC input can be damaged
• D. The comparator changes its output state

E1B02

2. Which of the following is an acceptable bandwidth for digital voice or slow-scan TV transmissions made on the HF amateur bands?

• A. 10 kHz
• B. 20 kHz
• C. 3 kHz
• D. 15 kHz

E7D03

3. What device is used as a stable voltage reference?

• A. An analog-to-digital converter
• B. An SCR
• C. A Zener diode
• D. A digital-to-analog converter

E8B05

4. What is the deviation ratio of an FM phone signal having a maximum frequency swing of plus or minus 5 kHz if the highest modulation frequency is 3 kHz?

• A. 6
• B. 0.167
• C. 1.67
• D. 0.6

E9C06

5. What is the effect of adding a terminating resistor to a rhombic or long-wire antenna?

• A. It changes the radiation pattern from bidirectional to unidirectional
• B. It changes the radiation pattern from horizontal to vertical polarization
• C. It reflects the standing waves on the antenna elements back to the transmitter
• D. It decreases the ground loss

E7C04

6. How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

• A. It introduces transconductance to cancel the reactive part of impedance
• B. It introduces negative resistance to cancel the resistive part of impedance
• C. Reactive currents are dissipated in matched resistances
• D. It cancels the reactive part of the impedance and changes the resistive part to the desired value

E6B03

7. What property of an LED's semiconductor material determines its forward voltage drop?

• A. Junction depth
• B. Junction capacitance
• C. Band gap
• D. Intrinsic resistance

E9F09

8. What impedance does a 1/4-wavelength transmission line present to an RF generator when the line is shorted at the far end?

• A. The same as the characteristic impedance of the transmission line
• B. Very high impedance
• C. Very low impedance
• D. The same as the generator output impedance

E9A11

9. Which of the following determines ground losses for a ground-mounted vertical antenna operating on HF?

• A. The standing wave ratio
• B. Take-off angle
• C. Soil conductivity
• D. Distance from the transmitter

E8A08

10. Why are direct or flash conversion analog-to-digital converters used for a software defined radio?

• A. Very high speed allows digitizing high frequencies
• B. Immunity to out-of-sequence coding reduces spurious responses
• C. Very low power consumption decreases frequency drift
• D. All these choices are correct

E9B04

11. What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

• A. 38 dB
• B. 3 dB
• C. 15 dB
• D. 28 dB

E7A05

12. Which of the following circuits continuously alternates between two states without an external clock signal?

• A. Monostable multivibrator
• B. T flip-flop
• C. Astable multivibrator
• D. J-K flip-flop

E8C05

13. What is the approximate bandwidth of a 13-WPM International Morse Code transmission?

• A. 13 Hz
• B. 52 Hz
• C. 26 Hz
• D. 104 Hz

E7B10

14. In Figure E7-1, what is the purpose of R1 and R2?

• A. Voltage divider bias
• B. Feedback
• C. Self bias
• D. Load resistors

E9D09

15. What is the function of a loading coil in an electrically short antenna?

• A. To lower the losses
• B. To increase the SWR bandwidth by increasing net reactance
• C. To resonate the antenna by cancelling the capacitive reactance
• D. To lower the Q

E3C08

16. Which of the following is the space-weather term for an extreme geomagnetic storm?

• A. X5
• B. M9
• C. B9
• D. G5

E3A13

17. Which of these emission modes is best for auroral propagation?

• A. SSB
• B. RTTY
• C. CW
• D. FM

E9E08

18. What is a use for a Wilkinson divider?

• A. To divide the frequency of the input to a counter to increase its frequency range
• B. To divide the operating frequency of a transmitter signal so it can be used on a lower frequency band
• C. To divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance
• D. To feed high-impedance antennas from a low-impedance source

E9G01

19. Which of the following can be calculated using a Smith chart?

• A. Radiation resistance
• B. Antenna radiation pattern
• C. Impedance along transmission lines
• D. Radio propagation

E7F11

20. What sets the minimum detectable signal level for a direct-sampling software defined receiver in the absence of atmospheric or thermal noise?

• A. Missing codes and jitter
• B. Reference voltage level and sample width in bits
• C. Data storage transfer rate
• D. Sample clock phase noise

E1D11

21. Which amateur stations are eligible to operate as Earth stations?

• A. Any amateur station, subject to the privileges of the class of operator license held by the control operator
• B. Any amateur licensee who has successfully completed the AMSAT space communications course
• C. Only those of General, Advanced or Amateur Extra class operators
• D. Only those of Amateur Extra class operators

E2C09

22. What type of equipment is commonly used to implement an amateur radio mesh network?

• A. A wireless router running custom firmware
• B. A computer running EchoLink to provide interface from the radio to the internet
• C. A 440 MHz transceiver with a 9,600-baud modem
• D. A 2-meter VHF transceiver with a 1,200-baud modem

E7E01

23. Which of the following can be used to generate FM phone signals?

• A. Balanced modulation of a local oscillator
• B. Balanced modulation of the audio amplifier
• C. Reactance modulation of the final amplifier
• D. Reactance modulation of a local oscillator

E2E01

24. Which of the following types of modulation is used for data emissions below 30 MHz?

• A. FSK
• B. Pulse modulation
• C. Spread spectrum
• D. DTMF tones modulating an FM signal

E7G08

25. How does the gain of an ideal operational amplifier vary with frequency?

• A. It does not vary with frequency
• B. It decreases logarithmically with increasing frequency
• C. It increases linearly with increasing frequency
• D. It decreases linearly with increasing frequency

E5C11

26. Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

• A. Point 1
• B. Point 8
• C. Point 3
• D. Point 7

E5D10

27. As a conductor's diameter increases, what is the effect on its electrical length?

• A. It varies randomly
• B. It increases
• C. It decreases
• D. Thickness has no effect on electrical length

E2B11

28. What is the function of the vertical interval signaling (VIS) code sent as part of an SSTV transmission?

• A. To provide vertical synchronization
• B. To lock the color burst oscillator in color SSTV images
• C. To identify the call sign of the station transmitting
• D. To identify the SSTV mode being used

E1E03

29. What is a Volunteer Examiner Coordinator?

• A. The person who has entered into an agreement with the FCC to be the VE session manager
• B. An organization that has entered into an agreement with the FCC to coordinate, prepare, and administer amateur operator license examinations
• C. A person who has volunteered to administer amateur operator license examinations
• D. An organization paid by the volunteer examiner team to publicize and schedule examinations

E4E05

30. What is used to suppress radio frequency interference from a line-driven AC motor?

• A. A brute-force AC-line filter in series with the motor's power leads
• B. A bypass choke in parallel with the motor's field winding
• C. A high-pass filter in series with the motor's power leads
• D. A bypass capacitor in series with the motor's field winding

E1C12

31. In what portion of the 630-meter band are phone emissions permitted?

• A. Only the bottom 3 kHz
• B. Only the top 3 kHz
• C. None
• D. The entire band

E1A02

32. When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

• A. 3 kHz above the lower band edge
• B. 1 kHz above the lower band edge
• C. 300 Hz above the lower band edge
• D. The exact lower band edge

E2A11

33. What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

• A. An isotropic antenna
• B. A circularly polarized antenna
• C. A linearly polarized antenna
• D. A log-periodic dipole array

E6A03

34. Why does a PN-junction diode not conduct current when reverse biased?

• A. Only N-type semiconductor material can conduct current
• B. Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
• C. Only P-type semiconductor material can conduct current
• D. Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator

E8D05

35. What is the most common method of reducing key clicks?

• A. Insert high-pass filters at the transmitter output
• B. Insert low-pass filters at the transmitter output
• C. Increase keying waveform rise and fall times
• D. Reduce keying waveform rise and fall times

E6E10

36. What advantage does surface-mount technology offer at RF compared to using through-hole components?

• A. Smaller circuit area
• B. Components have less parasitic inductance and capacitance
• C. All these choices are correct
• D. Shorter circuit board traces

E7H13

37. Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

• A. Use a temperature-controlled high Q dielectric resonator
• B. All these choices are correct
• C. Use a GPS signal reference
• D. Use a rubidium stabilized reference oscillator

E6D06

38. What core material property determines the inductance of an inductor?

• A. Permittivity
• B. Resistance
• C. Reactivity
• D. Permeability

E5A12

39. What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

• A. 218.3 kHz
• B. 436.6 kHz
• C. 31.4 kHz
• D. 15.7 kHz

E9H03

40. What is receiving directivity factor (RDF)?

• A. Forward gain compared to the gain in the reverse direction
• B. Relative directivity compared to a dipole
• C. Peak antenna gain compared to average gain over the hemisphere around and above the antenna
• D. Relative directivity compared to isotropic

E3B04

41. What are "extraordinary" and "ordinary" waves?

• A. Long-path and short-path waves
• B. Independently propagating, elliptically polarized waves created in the ionosphere
• C. Extraordinary waves exhibit rare long-skip propagation, compared to ordinary waves, which travel shorter distances
• D. Refracted rays and reflected waves

E6F08

42. Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits?

• A. Optoisolators eliminate the effects of reflected light in the control circuit
• B. Optoisolators provide a low-impedance link between a control circuit and a power circuit
• C. Optoisolators provide an electrical isolation between a control circuit and the circuit being switched
• D. Optoisolators provide impedance matching between the control circuit and power circuit

E2D06

43. Which of the following is a method for establishing EME contacts?

• A. Judging optimum transmission times by monitoring beacons reflected from the moon
• B. Storing and forwarding digital messages
• C. High-speed CW identification to avoid fading
• D. Time-synchronous transmissions alternating between stations

E4A05

44. What is the purpose of using a prescaler with a frequency counter?

• A. Amplify low-level signals for more accurate counting
• B. Prevent oscillation in a low-frequency counter circuit
• C. Multiply a higher frequency signal so a low-frequency counter can display the operating frequency
• D. Reduce the signal frequency to within the counter's operating range

E0A05

45. What hazard is created by operating at microwave frequencies?

• A. Microwaves are in the frequency range where wave velocity is higher
• B. The extremely high frequency energy can damage the joints of antenna structures
• C. The high gain antennas commonly used can result in high exposure levels
• D. Microwaves are ionizing radiation

E4B05

46. What three test loads are used to calibrate an RF vector network analyzer?

• A. Short circuit, open circuit, and resonant circuit
• B. Short circuit, open circuit, and 50 ohms
• C. 50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
• D. 50 ohms, 75 ohms, and 90 ohms

E4D05

47. What transmitter frequencies would create an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

• A. 146.88 MHz and 146.34 MHz
• B. 146.30 MHz and 146.90 MHz
• C. 146.34 MHz and 146.61 MHz
• D. 146.10 MHz and 147.30 MHz

E4C02

48. Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

• A. A properly adjusted product detector
• B. A front-end filter or preselector
• C. A notch filter
• D. A narrow IF filter

E5B08

49. What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 300 ohms, R is 100 ohms, and XL is 100 ohms?

• A. 27 degrees with the voltage lagging the current
• B. 63 degrees with the voltage leading the current
• C. 27 degrees with the voltage leading the current
• D. 63 degrees with the voltage lagging the current

E1F06

50. Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

• A. To allow a licensee who has passed an upgrade exam to operate with upgraded privileges while waiting for posting on the FCC database
• B. To provide for experimental amateur communications
• C. To allow a VE group with less than three VEs to administer examinations in a remote, sparsely populated area
• D. To allow use of a special event call sign