US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Only commercial transmitters
B	Each transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded.
C	Each transmitter operating with a duty cycle greater than 50 percent
D	Only the most powerful transmitter

2. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	50 watts PEP effective radiated power relative to a dipole
B	50 watts PEP effective radiated power relative to an isotropic radiator
C	100 watts PEP effective radiated power relative to an isotropic radiator
D	100 watts PEP effective radiated power relative to the gain of a half-wave dipole

3. - E1B02

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	15 kHz
B	10 kHz
C	3 kHz
D	20 kHz

4. - E1C04

What is meant by IARP?

Select	Answer
A	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
B	An indication of increased antenna reflected power
C	A forecast of intermittent aurora radio propagation
D	The internal amateur radio practices policy of the FCC

5. - E1D07

Which HF amateur bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40, 20, 17, 15, 12, and 10 meter bands
B	Only the 40, 30, 20, 15, 12, and 10 meter bands
C	All HF bands
D	Only the 40, 20, 17, 15, and 10 meter bands

6. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	The prospective VE obtains accreditation from the FCC
B	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
C	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
D	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner

7. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	440 MHz - 450 MHz
B	53 MHz - 54 MHz
C	222 MHz - 223 MHz
D	420 MHz - 430 MHz

8. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The location of the ground control station
B	The polarization of uplink and downlink signals
C	The uplink and downlink frequency ranges
D	Power limits for uplink and downlink transmissions

9. - E2B04

How is color information sent in analog SSTV?

Select	Answer
A	Color is amplitude modulated on the frequency modulated intensity signal
B	Color is sent in a color burst at the end of each line
C	Color information is sent on a 2.8 kHz subcarrier
D	Color lines are sent sequentially

10. - E2C05

What is the function of a DX QSL Manager?

Select	Answer
A	To allocate frequencies for DXpeditions
B	To run a net to allow many stations to contact a rare DX station
C	To handle the receiving and sending of confirmation cards for a DX station
D	To relay calls to and from a DX station

11. - E2D09

What type of modulation is used for JT65 contacts?

Select	Answer
A	IEEE 802.11
B	RTTY
C	PSK
D	Multi-tone AFSK

12. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK occupies less bandwidth
B	Direct FSK applies the data signal to the transmitter VFO, while AFSK transmits tones via phone
C	Only direct FSK can be decoded by computer
D	Direct FSK can transmit faster baud rates

13. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Wind shear
B	The jet stream
C	Temperature inversion
D	Dust devil

14. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Morning
B	Late at night
C	Noon
D	Afternoon or early evening

15. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	Four times as great
B	10 percent greater
C	50 percent greater
D	Twice as great

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Network analyzer
B	Bit error rate tester
C	Logic analyzer
D	Modulation monitor

17. - E4B05

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

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

18. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a superheterodyne HF or VHF communications receiver?

Select	Answer
A	Fewer components in the receiver
B	Improved receiver noise figure
C	Reduced drift
D	Easier for front-end circuitry to eliminate image responses

19. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To increase rejection of signals outside the desired band
B	To provide a range of AGC time constants
C	To allow selection of the optimum RF amplifier device
D	To store often-used frequencies

20. - E4E05

How can radio frequency interference from an AC motor be suppressed?

Select	Answer
A	By using a ground-fault current interrupter in the circuit used to power the motor
B	By installing a brute-force AC-line filter in series with the motor leads
C	By installing a high-pass filter in series with the motor's power leads
D	By installing a bypass capacitor in series with the motor leads

21. - E5A16

What is the resonant frequency of an RLC circuit if R is 33 ohms, L is 50 microhenries and C is 10 picofarads?

Select	Answer
A	7.12 kHz
B	23.5 kHz
C	7.12 MHz
D	23.5 MHz

22. - E5B05

What happens to the magnitude of a pure reactance when it is converted to a susceptance?

Select	Answer
A	It is shifted by 90 degrees
B	It is unchanged
C	The sign is reversed
D	It becomes the reciprocal

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

Select	Answer
A	+jX
B	Omega
C	Delta
D	-jX

24. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In a direction opposite to the current
B	In a circle around the conductor
C	In the same direction as the current
D	In all directions; omni-directional

25. - E6A01

In what application is gallium arsenide used as a semiconductor material?

Select	Answer
A	In very low-frequency RF circuits
B	In high-current rectifier circuits
C	In high-power audio circuits
D	In microwave circuits

26. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A negative resistance region
B	An internal capacitance that varies with the applied voltage
C	A constant voltage drop under conditions of varying current
D	A constant current drop under conditions of varying voltage

27. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To prevent input noise from causing unstable output signals
B	To allow the comparator to be used with AC input signals
C	To increase the sensitivity
D	To cause the output to change states continually

28. - E6D01

Why should core saturation of an impedance matching transformer be avoided?

Select	Answer
A	Magnetic flux would increase with frequency
B	Temporary changes of the core permeability could result
C	Harmonics and distortion could result
D	RF susceptance would increase

29. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Silicon nitride
B	Silicon
C	Silicon dioxide
D	Gallium nitride

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

Select	Answer
A	1.5 V
B	12 V
C	0.5 V
D	0.1 V

31. - E7A01

Which circuit is bistable?

Select	Answer
A	An AND gate
B	A flip-flop
C	A bipolar amplifier
D	An OR gate

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	Low input impedance
B	Low bandwidth
C	High power gain
D	High filament voltage

33. - E7C07

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50-ohm unbalanced output?

Select	Answer
A	A Pi-network with an additional series inductor on the output
B	A matching network in which all components are isolated from ground
C	A Phase Inverter Load network
D	A network with only three discrete parts

34. - E7D02

What is a characteristic of a switching electronic voltage regulator?

Select	Answer
A	The controlled device's duty cycle is changed to produce a constant average output voltage
B	It gives a ramp voltage at its output
C	The resistance of a control element is varied in direct proportion to the line voltage or load current
D	It is generally less efficient than a linear regulator

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

Select	Answer
A	An FM generator circuit
B	A circuit for filtering two closely adjacent signals
C	A circuit for detecting FM signals
D	An automatic band-switching circuit

36. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A crystal-lattice filter
B	A Hilbert-transform filter
C	A phase-inverting filter
D	An adaptive filter

37. - E7G02

What is ringing in a filter?

Select	Answer
A	Undesired oscillations added to the desired signal
B	A reduction in high frequency response
C	An echo caused by a long time delay
D	Partial cancellation of the signal over a range of frequencies

38. - E7H10

What information is contained in the lookup table of a direct digital synthesizer (DDS)?

Select	Answer
A	The phase relationship between a reference oscillator and the output waveform
B	Amplitude values that represent the desired waveform
C	Frequently used receiver and transmitter frequencies
D	The phase relationship between a voltage-controlled oscillator and the output waveform

39. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	1 to 1
B	2.5 to 1
C	25 to 1
D	100 to 1

40. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	2.14
B	0.47
C	0.214
D	47

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

Select	Answer
A	IF bandwidth and Q
B	Modulation index and output power
C	Keying speed and shape factor (rise and fall time)
D	All these choices are correct

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
B	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
C	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
D	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

Select	Answer
A	632 watts
B	159 watts
C	252 watts
D	63.2 watts

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

Select	Answer
A	50 degrees
B	30 degrees
C	75 degrees
D	25 degrees

45. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	A dipole constructed from zip cord
B	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
C	An end-fed dipole antenna
D	An omni-directional antenna commonly used for satellite communications

46. - E9D01

How much does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	4 dB
B	6 dB
C	3 dB
D	2 dB

47. - E9E07

What parameter describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Reflection coefficient
B	Velocity factor
C	Characteristic impedance
D	Dielectric constant

48. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

Select	Answer
A	10.6 meters
B	8.5 meters
C	13.3 meters
D	7.0 meters

49. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Voltage lines and current chords
B	Resistance circles and reactance arcs
C	Resistance lines and reactance chords
D	Voltage circles and current arcs

50. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	Antenna headings from several different receiving locations are used to locate the signal source
B	The geometric angles of sky waves from the source are used to determine its position
C	A fixed receiving station uses three different antennas to plot the location of the signal source
D	A fixed receiving station plots three headings to the signal source

Figure E9-1