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

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1. - E0A05

What is one of the potential hazards of operating in the amateur radio microwave bands?

Select	Answer
A	The high gain antennas commonly used can result in high exposure levels
B	The extremely high frequency energy can damage the joints of antenna structures
C	Microwaves are ionizing radiation
D	Microwaves often travel long distances by ionospheric reflection

2. - E1A07

What is the maximum power permitted on the 2200 meter band?

Select	Answer
A	5 watts EIRP (Equivalent isotropic radiated power)
B	100 watts PEP
C	50 watts PEP
D	1 watt EIRP (Equivalent isotropic radiated power)

3. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You must obtain a construction permit from the airport zoning authority
B	You must file an Environmental Impact Statement with the EPA before construction begins
C	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules
D	You must submit engineering drawings to the FAA

4. - E1C01

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	170 Hz
B	1.5 kHz
C	60 Hz
D	2.8 kHz

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

Select	Answer
A	All these choices are correct
B	A message forwarding station or automatically controlled digital station
C	A local repeater or linked repeater station
D	A space station, beacon station, or telecommand station

6. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	A sentence of up to one year in prison
B	All these choices are correct
C	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
D	A fine of up to $1000 per occurrence

7. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications that have religious content
B	Communications transmitted for hire or material compensation, except as otherwise provided in the rules
C	Communications that have political content, except as allowed by the Fairness Doctrine
D	Communications in a language other than English

8. - E2A13

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Node hopping
B	Digipeating
C	Multi-satellite relaying
D	Store-and-forward

9. - E2B05

Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?

Select	Answer
A	The vestigial sideband carries the audio information
B	The vestigial sideband contains chroma information
C	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
D	Vestigial sideband provides high frequency emphasis to sharpen the picture

10. - E2C04

Which of the following frequencies are sometimes used for amateur radio mesh networks?

Select	Answer
A	Frequencies shared with various unlicensed wireless data services
B	Cable TV channels 41 through 43
C	HF frequencies where digital communications are permitted
D	The 60 meter band channel centered on 5373 kHz

11. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	Use of special digital modes
B	Short transmissions with rapidly repeated call signs and signal reports
C	All these choices are correct
D	15-second timed transmission sequences with stations alternating based on location

12. - E2E03

How is the timing of FT4 contacts organized?

Select	Answer
A	Stations take turns on alternate days
B	By exchanging ACK/NAK packets
C	Alternating transmissions at 7.5 second intervals
D	It depends on the lunar phase

13. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The E layer
B	The F2 layer
C	The F1 layer
D	The D layer

14. - E3B07

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become elliptically polarized
B	They become phase locked
C	They become depolarized
D	They are bent toward the magnetic poles

15. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	An extreme geomagnetic storm
B	Very low solar activity
C	Moderate solar wind
D	Waning sunspot numbers

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and time
B	RF amplitude and frequency
C	SWR and time
D	SWR and frequency

17. - E4B04

Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

Select	Answer
A	S21
B	S11
C	S22
D	S12

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

Select	Answer
A	The noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity
B	Receiver power consumption can be reduced when wider bandwidth is not required
C	Receive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference
D	Multiple frequencies can be received simultaneously if desired

19. - E4D08

What causes intermodulation in an electronic circuit?

Select	Answer
A	Positive feedback
B	Too little gain
C	Lack of neutralization
D	Nonlinear circuits or devices

20. - E4E06

What is one type of electrical interference that might be caused by a nearby personal computer?

Select	Answer
A	A whining type noise that continually pulses off and on
B	A clicking noise at intervals of a few seconds
C	A loud AC hum in the audio output of your station receiver
D	The appearance of unstable modulated or unmodulated signals at specific frequencies

21. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	R/L
B	L/R
C	Minimum
D	Maximum

22. - E5B12

What is admittance?

Select	Answer
A	The inverse of impedance
B	The turns ratio of a transformer
C	The term for the gain of a field effect transistor
D	The inverse of Q factor

23. - E5C11

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?

Select	Answer
A	Point 1
B	Point 7
C	Point 8
D	Point 3

24. - E5D15

What is the power factor of an RL circuit having a 45-degree phase angle between the voltage and the current?

Select	Answer
A	0.707
B	0.5
C	0.866
D	1.0

25. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	N-type impurity
B	Donor impurity
C	Insulator impurity
D	Acceptor impurity

26. - E6B08

Which of the following is a Schottky barrier diode?

Select	Answer
A	Metal-semiconductor junction
B	Electrolytic rectifier
C	Thermionic emission diode
D	PIN junction

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	3
B	4
C	1
D	2

28. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Select	Answer
A	Powdered-iron cores generally have greater initial permeability
B	Powdered-iron cores generally require fewer turns to produce a given inductance
C	Powdered-iron cores use smaller diameter wire for the same inductance
D	Powdered-iron cores generally maintain their characteristics at higher currents

29. - E6E10

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

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

30. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Selenium
B	Silicon
C	Cadmium Sulfide
D	Copper oxide

31. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic 1 at its output only if all inputs are logic 1
B	It produces logic 0 at its output if only one input is logic 1
C	It produces logic 1 at its output if only one input is logic 1
D	It produces logic 0 at its output only if all inputs are logic 0

32. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	Where the load line intersects the voltage axis
B	Approximately halfway between saturation and cutoff
C	At a point where the bias resistor equals the load resistor
D	At a point where the load line intersects the zero bias current curve

33. - E7C08

Which of the following factors has the greatest effect on the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The gain of the RF stage preceding the filter
B	The amplitude of the signals passing through the filter
C	The DC voltage applied to the quartz crystal
D	The relative frequencies of the individual crystals

34. - E7D10

What is the primary reason that a high-frequency switching type high-voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	The inverter design does not require any output filtering
B	It uses a diode bridge rectifier for increased output
C	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
D	It uses a large power factor compensation capacitor to recover power from the unused portion of the AC cycle

35. - E7E07

What is meant by the term "baseband" in radio communications?

Select	Answer
A	The lowest frequency band that the transmitter or receiver covers
B	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
C	The frequency range occupied by a message signal prior to modulation
D	The unmodulated bandwidth of the transmitted signal

36. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At least half the rate of the highest frequency component of the signal
B	At the same rate as the highest frequency component of the signal
C	At four times the rate of the highest frequency component of the signal
D	At least twice the rate of the highest frequency component of the signal

37. - E7G05

How can unwanted ringing and audio instability be prevented in an op-amp RC audio filter circuit?

Select	Answer
A	Increase both gain and Q
B	Restrict Q but increase gain
C	Restrict gain but increase Q
D	Restrict both gain and Q

38. - E7H13

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

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

39. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The frequency of the modulating signal
B	Speech characteristics
C	The degree of carrier suppression
D	Amplifier gain

40. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
B	Two or more signals are arranged to share discrete time slots of a data transmission
C	Two or more signals are quadrature modulated to increase bandwidth efficiency
D	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	4.8 kHz
B	15.36 kHz
C	9.6 kHz
D	5.76 kHz

42. - E8D02

What spread spectrum communications technique uses a high-speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Frequency hopping
B	Binary phase-shift keying
C	Direct sequence
D	Phase compandored spread spectrum

43. - E9A13

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Power factor
B	Effective radiated power
C	Apparent power
D	Half-power bandwidth

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

Select	Answer
A	15 dB
B	3 dB
C	28 dB
D	38 dB

45. - E9C03

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed in phase?

Select	Answer
A	A Figure-8 end-fire along the axis of the array
B	Cardioid
C	A Figure-8 broadside to the axis of the array
D	Omni-directional

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
B	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
C	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
D	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

Select	Answer
A	All these choices are correct
B	Gamma match
C	Double-bazooka match
D	Hairpin match

48. - E9F09

What is the approximate physical length of a foam polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 7.2 MHz?

Select	Answer
A	10.4 meters
B	8.3 meters
C	5.2 meters
D	6.9 meters

49. - E9G01

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

Select	Answer
A	Impedance along transmission lines
B	Antenna radiation pattern
C	Radio propagation
D	Radiation resistance

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

Select	Answer
A	Broadband response
B	High radiation angle
C	A very sharp peak
D	A very sharp single null

Figure E5-1

Figure E6-3