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

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1. - E1A02

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?

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

2. - 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 may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
B	You must obtain a construction permit from the airport zoning authority
C	No special rules apply if your antenna structure will be less than 300 feet in height
D	You must file an Environmental Impact Statement with the EPA before construction begins

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	A station operating with its output power controlled automatically
B	The use of a control link between a control point and a locally controlled station
C	The use of devices and procedures for control so that the control operator does not have to be present at a control point
D	Remotely controlling a station's antenna pattern through a directional control link

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	70 cm only
B	33 cm and 13 cm
C	70 cm and 13 cm
D	70 cm and 33 cm

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
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 amateur operator license examinations
C	A person who has volunteered to prepare amateur operator license examinations
D	A person who has volunteered to administer amateur operator license examinations

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A04

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

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

8. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	A special notch filter to remove synchronization pulses
B	A special IF converter
C	A special front end limiter
D	No other hardware is needed

9. - E2C02

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

Select	Answer
A	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
B	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
C	A manual technique 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. - E2D05

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

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

11. - E2E09

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

Select	Answer
A	MT63
B	PSK31
C	RTTY
D	PACTOR

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	The returning echo is several Hertz lower in frequency than the transmitted signal
B	A gradual loss of signal as the Sun rises
C	A fluttery irregular fading
D	A slow change in the pitch of the CW signal

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	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
C	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves
D	In darkness, solar absorption drops greatly while atmospheric ionization remains steady

14. - E3C08

What does the space weather term G5 mean?

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

15. - E4A08

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

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

16. - E4B17

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

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

17. - 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	-164 dBm
B	-155 dBm
C	-148 dBm
D	-174 dBm

18. - E4D05

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

Select	Answer
A	146.34 MHz and 146.61 MHz
B	146.10 MHz and 147.30 MHz
C	146.88 MHz and 146.34 MHz
D	173.35 MHz and 139.40 MHz

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	An electrical-sparking signal
B	Harmonics of the AC power line frequency
C	A common-mode signal at the frequency of the radio transmitter
D	A differential-mode signal at the AC power line frequency

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	44.72 MHz
B	22.36 MHz
C	1.78 MHz
D	3.56 MHz

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

Select	Answer
A	The susceptance phase angle is the inverse of the reactance phase angle
B	The sign is reversed
C	It is unchanged
D	It is shifted by 90 degrees

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Phasor diagram
B	Near field diagram
C	Far field diagram
D	Venn diagram

23. - E5D04

Why are short connections necessary at microwave frequencies?

Select	Answer
A	To increase neutralizing resistance
B	To reduce noise figure
C	Because of ground reflections
D	To reduce phase shift along the connection

24. - 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	Acceptor impurity
C	Insulator impurity
D	Donor impurity

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	6
B	5
C	7
D	1

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	Programmable equipment used for testing digital logic integrated circuits
B	A device to control industrial equipment
C	An algorithm for simulating logic functions during circuit design
D	A programmable collection of logic gates and circuits in a single integrated circuit

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Ferrite beads
B	Electrolytic capacitors
C	Steel-core toroids
D	Butterworth filters

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	DIP
B	SOT
C	PLCC
D	Ball grid array

29. - E6F07

What is a solid state relay?

Select	Answer
A	A device that uses semiconductors to implement the functions of an electromechanical relay
B	A mechanical relay that latches in the on or off state each time it is pulsed
C	A passive delay line
D	A relay using transistors to drive the relay coil

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It decodes a decimal number for display on a seven segment LED display
B	It produces ten output pulses for every input pulse
C	It adds two decimal numbers together
D	It produces one output pulse for every ten input pulses

31. - E7B13

In Figure E7-2, what is the purpose of R?

Select	Answer
A	Emitter load
B	Voltage regulation
C	Collector load
D	Fixed bias

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A power supply filter made with interlaced quartz crystals
B	An audio filter made with four quartz crystals that resonate at 1kHz intervals
C	A filter with narrow bandwidth and steep skirts made using quartz crystals
D	A filter with wide bandwidth and shallow skirts made using quartz crystals

33. - 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	Matching of day and night charge rates
D	Prevention of battery undercharge

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

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

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

Select	Answer
A	It removes low frequency signal components to eliminate the need for DC restoration
B	It removes high-frequency signal components which would otherwise be reproduced as lower frequency components
C	It notches out the sampling frequency to avoid sampling errors
D	It peaks the response of the decimator, improving bandwidth

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The output voltage of the op-amp minus its input voltage
B	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
C	The differential input voltage needed to bring the open loop output voltage to zero
D	The potential between the amplifier input terminals of the op-amp in an open loop condition

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A hybrid synthesizer
B	A phase locked loop synthesizer
C	A direct digital synthesizer
D	A diode-switching matrix synthesizer

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	8
B	256 divided by the gain of the input amplifier
C	256
D	8 multiplied by the gain of the input amplifier

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
B	A frequency modulation technique which uses non-harmonically related frequencies
C	A bandwidth compression technique using Fourier transforms
D	A digital mode for narrow band, slow speed transmissions

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, a retransmission is requested
B	If errors are detected, redundant data is substituted
C	Special binary codes provide automatic correction
D	Special polynomial codes provide automatic correction

41. - E8D10

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

Select	Answer
A	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
B	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
C	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
D	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Half-wave dipole
B	Yagi
C	Quarter-wave vertical
D	Isotropic antenna

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	Antenna gain
B	SWR vs frequency charts
C	Polar plots of the far field elevation and azimuth patterns
D	All of these choices are correct

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

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

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	A resistive wire, such as spark plug wire
B	A wide flat copper strap
C	A cable with six or seven 18 gauge conductors in parallel
D	A single 12 gauge or 10 gauge stainless steel wire

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	A series capacitor
B	A shunt inductor
C	Pi-network
D	Pi-L-network

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

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

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Prime axis
B	Polar axis
C	Reactance axis
D	Impedance axis

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A vertical antenna coupled to a feed line through an inductive loop of wire
B	One or more turns of wire wound in the shape of a large open coil
C	A small coil of wire tightly wound around a toroidal ferrite core
D	A large circularly polarized antenna

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

Figure E6-3

Figure E7-2

Figure E9-3