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

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1. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	All these choices are correct
B	Ground reflections and scattering make the field strength vary with location
C	E field and H field radiation intensity peaks can occur at different locations
D	The body reacts to electromagnetic radiation from both the E and H fields

2. - E1A05

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

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

3. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	All amateur service frequencies authorized to the control operator
B	Specific local government channels
C	Specific segments in the amateur service MF, HF, VHF and UHF bands
D	Military Auxiliary Radio System (MARS) channels

4. - E1C04

What is meant by IARP?

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

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

Select	Answer
A	100 watts
B	1 watt
C	5 watts
D	2 watts

6. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and send the documents to the NCVEC for grading
B	They must collect and send the documents to the FCC according to instructions
C	They must collect and submit the documents to the coordinating VEC for grading
D	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions

7. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	The equipment dealer assembled it from a kit
B	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
C	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
D	It was imported from a manufacturer in another country and was certificated by that country's government

8. - E2A11

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

Select	Answer
A	A log-periodic dipole array
B	An isotropic antenna
C	A linearly polarized antenna
D	A circularly polarized antenna

9. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	90
B	60
C	120
D	30

10. - E2C01

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control and the remote transmitter is located in the U.S.?

Select	Answer
A	No additional indicator is required
B	/ followed by the ARRL Section of the remote station
C	/R# where # is the district of the remote station
D	/ followed by the USPS two-letter abbreviation for the state in which the remote station is located

11. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Connect
B	Unnumbered Information
C	Disconnect
D	Acknowledgement

12. - E2E12

How do ALE stations establish contact?

Select	Answer
A	ALE radios send a constant tone code to establish a frequency for future use
B	ALE radios monitor an internet site for the frequency they are being paged on
C	ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received
D	ALE radios activate when they hear their signal echoed by back scatter

13. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by EME?

Select	Answer
A	2000 miles, if the moon is at apogee
B	500 miles, if the moon is at perigee
C	5000 miles, if the moon is at perigee
D	12,000 miles, if the moon is visible by both stations

14. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Successive ionospheric refractions without an intermediate reflection from the ground
B	Propagation across the geomagnetic equator
C	Propagation away from the great circle bearing between stations
D	Signals reflected back toward the transmitting station

15. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Increasing disruption of the geomagnetic field
B	Decreasing disruption of the geomagnetic field
C	Higher levels of solar UV radiation
D	An increase in the critical frequency

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

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

17. - E4B08

Which of the following can be used to measure the Q of a series-tuned circuit?

Select	Answer
A	The inductance to capacitance ratio
B	The resonant frequency of the circuit
C	The frequency shift
D	The bandwidth of the circuit's frequency response

18. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

Select	Answer
A	-174 dBm
B	-164 dBm
C	-148 dBm
D	-155 dBm

19. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
B	When the signals from the transmitters are reflected in phase from airplanes passing overhead
C	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
D	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters

20. - E4E06

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

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

21. - E5A04

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

Select	Answer
A	Approximately equal to circuit resistance
B	Low compared to the circuit resistance
C	High compared to the circuit resistance
D	Approximately equal to inductive reactance

22. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	14 degrees with the voltage lagging the current
B	14 degrees with the voltage leading the current
C	76 degrees with the voltage leading the current
D	76 degrees with the voltage lagging the current

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

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

24. - E5D05

What is the power factor of an RL circuit having a 30-degree phase angle between the voltage and the current?

Select	Answer
A	0.5
B	0.866
C	0.577
D	1.73

25. - E6A11

In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	1
B	6
C	3
D	2

26. - E6B09

What is a common use for point-contact diodes?

Select	Answer
A	As an RF detector
B	As a constant current source
C	As a high-voltage rectifier
D	As a constant voltage source

27. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Lower power consumption
B	Differential output capability
C	Lower distortion
D	Immune to damage from static discharge

28. - E6D06

What core material property determines the inductance of an inductor?

Select	Answer
A	Permeability
B	Thermal impedance
C	Resistance
D	Reactivity

29. - E6E10

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

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

30. - E6F10

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

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

31. - E7A11

What type of logic defines "1" as a high voltage?

Select	Answer
A	Negative logic
B	Positive Logic
C	Reverse Logic
D	Assertive Logic

32. - E7B13

Which of the following describes an emitter follower (or common collector) amplifier?

Select	Answer
A	An amplifier with a low impedance output that follows the base input voltage
B	A two-transistor amplifier with the emitters sharing a common bias resistor
C	A differential amplifier with both inputs fed to the emitter of the input transistor
D	An OR circuit with only one emitter used for output

33. - E7C09

What is a crystal lattice filter?

Select	Answer
A	A power supply filter made with interlaced quartz crystals
B	A filter with narrow bandwidth and steep skirts made using quartz crystals
C	An audio filter made with four quartz crystals that resonate at 1 kHz intervals
D	A filter using lattice-shaped quartz crystals for high-Q performance

34. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Control of electrolyte levels during battery discharge
B	Prevention of battery damage due to overcharge
C	Prevention of battery undercharge
D	Matching of day and night charge rates

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

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

36. - E7F07

What function is performed by a Fast Fourier Transform?

Select	Answer
A	Converting analog signals to digital form
B	Converting digital signals to analog form
C	Converting 8-bit data to 16-bit data
D	Converting digital signals from the time domain to the frequency domain

37. - E7G01

What is the typical output impedance of an op-amp?

Select	Answer
A	100 ohms
B	Very high
C	1000 ohms
D	Very low

38. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Wide-band AF and RF power amplification
B	Photovoltaic conversion, optical coupling
C	Comparison of two digital input signals, digital pulse counter
D	Frequency synthesis, FM demodulation

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	25 to 1
C	2.5 to 1
D	100 to 1

40. - E8B09

What is deviation ratio?

Select	Answer
A	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
B	The ratio of the highest audio modulating frequency to the average audio modulating frequency
C	The ratio of the audio modulating frequency to the center carrier frequency
D	The ratio of the carrier center frequency to the audio modulating frequency

41. - E8C06

What is the bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	0.3 kHz
B	1.0 kHz
C	0.1 Hz
D	0.5 kHz

42. - E8D08

What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

Select	Answer
A	Repeat Request Rate (RRR)
B	Intermodulation Distortion (IMD)
C	Signal-to-noise ratio
D	Baud rate

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. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from a theoretical isotropic antenna, assuming each is driven by the same amount of power?

Select	Answer
A	The total amount of radiation from the directional antenna is increased by the gain of the antenna
B	The total amount of radiation from the directional antenna is stronger by its front-to-back ratio
C	The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
D	They are the same

45. - E9C12

Which of the following describes an Extended Double Zepp antenna?

Select	Answer
A	An end-fed folded dipole antenna
B	A center-fed 1.25-wavelength antenna (two 5/8-wave elements in phase)
C	A wideband vertical antenna constructed from precisely tapered aluminum tubing
D	A portable antenna erected using two push support poles

46. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	More common-mode current is present on the feed line
B	Gain is reduced
C	SWR bandwidth decreases
D	SWR bandwidth increases

47. - E9E09

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

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

48. - E9F13

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

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

49. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The resistance axis
B	The current axis
C	The reactance axis
D	The voltage axis

50. - E9H10

How can the output voltage of a multiple-turn receiving loop antenna be increased?

Select	Answer
A	By reducing the permeability of the loop shield
B	By increasing the number of turns and/or the area
C	By utilizing high impedance wire for the coupling loop
D	By winding adjacent turns in opposing directions

Figure E6-1

Figure E9-3