US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

Select	Answer
A	No, the sideband will extend beyond the edge of the phone band segment
B	Yes, because the DX station initiated the contact
C	Yes, because the displayed frequency is within the 75 meter phone band segment
D	No, U.S. stations are not permitted to use phone emissions below 3.610 MHz

2. - E1B10

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

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

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under local control there is no control operator
B	Under automatic control there is no control operator
C	Under automatic control the control operator is not required to be present at the control point
D	Under local control a control operator is not required to be present at a control point

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

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

5. - 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 submit the application document to the coordinating VEC according to the coordinating VEC instructions
C	They must collect and submit the documents to the coordinating VEC for grading
D	They must collect and send the documents to the FCC according to instructions

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Amateur Extra Class operators
B	Any licensed amateur operator
C	Only Technician, General, Advanced or Amateur Extra Class operators
D	Only General, Advanced or Amateur Extra Class operators

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The satellite's orientation with respect to the Earth
B	Whether the satellite is in a polar or equatorial orbit
C	The type of signals that can be relayed through the satellite
D	The satellite's uplink and downlink frequency bands

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
B	They are not permitted above 54 MHz
C	None; they are allowed on all amateur frequencies
D	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
B	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
C	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
D	The acceptable practice of manually posting the call signs of stations on a spotting network

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	PACTOR III
B	Olivia
C	FSK441
D	JT65

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	RTTY
B	PSK31
C	MT63
D	PACTOR

12. - E3A13

Which emission mode is best for aurora propagation?

Select	Answer
A	FM
B	SSB
C	RTTY
D	CW

13. - E3B10

What is the cause of gray-line propagation?

Select	Answer
A	At twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high
B	In darkness, solar absorption drops greatly while atmospheric ionization remains steady
C	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
D	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves

14. - E3C04

What does the value of Bz (B sub Z) represent?

Select	Answer
A	Direction and strength of the interplanetary magnetic field
B	Duration of long-delayed echoes
C	Geomagnetic field stability
D	Critical frequency for vertical transmissions

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	An ohmmeter
B	An antenna analyzer
C	A spectrum analyzer
D	A Q meter

16. - E4B13

Which S parameter is equivalent to forward gain?

Select	Answer
A	S22
B	S12
C	S21
D	S11

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

Select	Answer
A	RAM speed used for data storage
B	CPU register width in bits
C	Analog-to-digital converter sample width in bits
D	Anti-aliasing input filter bandwidth

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A Class C final amplifier
B	A properly terminated circulator at the output of the transmitter
C	A band-pass filter in the feed line between the transmitter and receiver
D	A Class D final amplifier

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By turning off the AC power line main circuit breaker and listening on a battery operated radio
B	By observing the AC power line voltage with a spectrum analyzer
C	By checking the power line voltage with a time domain reflectometer
D	By observing the AC power line waveform with an oscilloscope

20. - E5A03

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

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

21. - E5B06

What is susceptance?

Select	Answer
A	The magnetic impedance of a circuit
B	The inverse of reactance
C	A measure of the efficiency of a transformer
D	The ratio of magnetic field to electric field

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

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

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The ratio of the current to the resistance
B	The resistance divided by the current
C	The diameter of the conductor
D	The amount of current flowing through the conductor

24. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The change in collector current with respect to base current
B	The switching speed of the transistor
C	The breakdown voltage of the base to collector junction
D	The frequency at which the current gain is reduced to 1

25. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Insufficient forward voltage
B	Excessive inverse voltage
C	Charge carrier depletion
D	Excessive junction temperature

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A FET logic family based on bimetallic semiconductors
B	A logic family based on bismuth CMOS devices
C	A logic device with two CMOS circuits per package
D	An integrated circuit logic family using both bipolar and CMOS transistors

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores have lower Q characteristics
B	Toroidal cores exhibit greater hysteresis
C	Toroidal cores make it easier to couple the magnetic energy into other components
D	Toroidal cores confine most of the magnetic field within the core material

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Surface mount
B	Radial lead
C	Axial lead
D	TO-220

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Protons
B	Holes
C	Photons
D	Electrons

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Monostable multivibrator
B	Astable multivibrator
C	T flip-flop
D	J-K flip-flop

31. - E7B02

What is a Class D amplifier?

Select	Answer
A	A type of amplifier that uses switching technology to achieve high efficiency
B	An amplifier that uses drift-mode FETs for high efficiency
C	A low power amplifier that uses a differential amplifier for improved linearity
D	A frequency doubling amplifier

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Extremely flat response over its pass band with gradually rounded stop band corners
B	Gradual passband rolloff with extreme stop band ripple
C	Extremely sharp cutoff with one or more notches in the stop band
D	Gradual passband rolloff with minimal stop band ripple

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A series current source
B	A series regulator
C	A shunt current source
D	A shunt regulator

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A heterodyne suppressor
B	An audio prescaler
C	A pre-emphasis network
D	A de-emphasis network

35. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	A frequency synthesizer removes the unwanted sidebands
B	Emulation of quartz crystal filter characteristics
C	Mixing products are converted to voltages and subtracted by adder circuits
D	Combine signals with a quadrature phase relationship

36. - E7G05

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

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

37. - E7H02

Which describes a microphonic?

Select	Answer
A	Distortion caused by RF pickup on the microphone cable
B	Changes in oscillator frequency due to mechanical vibration
C	An IC used for amplifying microphone signals
D	Excess loading of the microphone by an oscillator

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	Human speech
B	All of these choices are correct
C	Video signals
D	Data

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	2000
B	6000
C	1/3
D	3

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The number of characters carried per second by the station-to-station link
B	The rate at which the waveform of a transmitted signal changes to convey information
C	The duration of each bit in a message sent over the air
D	The number of control characters in a message packet

41. - 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

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It increases arithmetically
B	It is essentially unaffected
C	It increases geometrically
D	It decreases

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region where radiated power dissipates over a specified time period
B	The region of the ionosphere where radiated power is not refracted
C	The region where the shape of the antenna pattern is independent of distance
D	The region where radiated field strengths are obstructed by objects of reflection

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	It is increased
B	It is decreased
C	No change occurs
D	It becomes flat

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	An SWR less than 1:1
B	A reflection coefficient greater than 1
C	A dielectric constant greater than 1
D	An SWR greater than 1:1

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	2.3 meters
B	3.5 meters
C	20 meters
D	0.2 meters

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning prime center with regard to the reactance axis
B	Reassigning reactance values with regard to the resistance axis
C	Reassigning impedance values with regard to the prime center
D	Reassigning resistance values with regard to the reactance axis

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	They must be erected at least 1/2 wavelength above the ground to attain good directivity
B	Atmospheric noise is so high that gain over a dipole is not important
C	All of these choices are correct
D	Low loss coax transmission line is essential for good performance

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

Select	Answer
A	Use an antenna modeling program to calculate field strength at accessible locations
B	Use a hand calculator plus Smith-chart equations to calculate the fields
C	All of the choices are correct
D	Use a calibrated antenna analyzer