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	Ground reflections and scattering make the field strength vary with location
B	All these choices are correct
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. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
B	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
C	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
D	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use

3. - E1B07

To what type of regulations does PRB-1 apply?

Select	Answer
A	FAA tower height limits
B	Use of wireless devices in vehicles
C	Homeowners associations
D	State and local zoning

4. - E1C06

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	You must identify in the official language of the country in which you are operating
B	You must append "/CEPT" to your call sign
C	The U.S. embassy must approve of your operation
D	You must bring a copy of FCC Public Notice DA 16-1048

5. - E1D07

Which HF amateur bands have frequencies authorized for space stations?

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

6. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Friends of the VE
B	All these choices are correct
C	Employees of the VE
D	Relatives of the VE as listed in the FCC rules

7. - E1F10

Who may be the control operator of an auxiliary station?

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

8. - E2A02

Which of the following occurs when a satellite is using an inverting linear transponder?

Select	Answer
A	All these choices are correct
B	Upper sideband on the uplink becomes lower sideband on the downlink, and vice versa
C	Doppler shift is reduced because the uplink and downlink shifts are in opposite directions
D	Signal position in the band is reversed

9. - E2B04

How is color information sent in analog SSTV?

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

10. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send the call sign of the DX station three times, the words this is,then your call sign three times
B	Send only the last two letters of your call sign until you make contact
C	Send your full call sign and grid square
D	Send your full call sign once or twice

11. - E2D05

What is one advantage of the JT65 mode?

Select	Answer
A	Uses only a 65 Hz bandwidth
B	Permits fast-scan TV transmissions over narrow bandwidth
C	The ability to decode signals which have a very low signal-to-noise ratio
D	Easily copied by ear if necessary

12. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Final Error Correction
B	Fatal Error Correction
C	Forward Error Correction
D	First Error Correction

13. - E3A12

What is the cause of auroral activity?

Select	Answer
A	Meteor showers concentrated in the extreme northern and southern latitudes
B	The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
C	The interaction in the F2 layer between the solar wind and the Van Allen belt
D	An extreme low-pressure area in the polar regions

14. - E3B11

At what time of day can sporadic E propagation occur?

Select	Answer
A	Only around sunset
B	Only around sunset and sunrise
C	Any time
D	Only in hours of darkness

15. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Polar
B	Transequatorial
C	Sporadic E
D	NVIS

16. - E4A02

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

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

17. - E4B05

What three test loads are used to calibrate an 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 50 ohms
D	Short circuit, open circuit, and resonant circuit

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

19. - E4D08

What causes intermodulation in an electronic circuit?

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

20. - E4E11

What could cause local AM broadcast band signals to combine to generate spurious signals in the MF or HF bands?

Select	Answer
A	One or more of the broadcast stations is transmitting an over-modulated signal
B	Your station receiver IF amplifier stage is defective
C	You are receiving skywave signals from a distant station
D	Nearby corroded metal joints are mixing and re-radiating the broadcast signals

21. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

Select	Answer
A	The voltage and current are in phase
B	The current leads the voltage by 90 degrees
C	The voltage leads the current by 90 degrees
D	The voltage and current are 180 degrees out of phase

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

Select	Answer
A	Voltage and current are in phase
B	Current leads voltage by 90 degrees
C	Voltage and current are 180 degrees out of phase
D	Voltage leads current by 90 degrees

23. - E5C04

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Rectangular coordinates
B	Faraday grid
C	Maidenhead grid
D	Elliptical coordinates

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 all directions; omni-directional
C	In a circle around the conductor
D	In the same direction as the current

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	5
B	2
C	6
D	4

26. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Silicon-controlled rectifier
B	Varactor diode
C	Zener diode
D	Tunnel diode

27. - E6C03

What is tri-state logic?

Select	Answer
A	Logic devices that utilize ternary math
B	Proprietary logic devices manufactured by Tri-State Devices
C	Low-power logic devices designed to operate at 3 volts
D	Logic devices with 0, 1, and high-impedance output states

28. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	The skin effect
B	Inter-turn capacitance
C	Inductive kickback
D	Non-linear core hysteresis

29. - E6E07

What type of transmission line is used for connections to MMICs?

Select	Answer
A	Miniature coax
B	Microstrip
C	Parallel wire
D	Circular waveguide

30. - E6F11

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

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

31. - E7A02

What is the function of a decade counter?

Select	Answer
A	It produces 10 output pulses for every input pulse
B	It decodes a binary number for display on a seven-segment LED display
C	It produces one output pulse for every 10 input pulses
D	It decodes a decimal number for display on a seven-segment LED display

32. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common collector
B	Emitter follower
C	Common emitter
D	Common base

33. - E7C12

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	L-networks cannot perform impedance transformation
B	The Q of Pi-networks can be controlled
C	Pi-networks provide balanced input and output
D	Pi-networks are more stable

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

Select	Answer
A	Minimum input voltage for rated power dissipation
B	Maximum that the output voltage may decrease at rated load
C	Minimum input-to-output voltage required to maintain regulation
D	Maximum output voltage drops when the input voltage is varied over its specified range

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. - E7F02

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

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

37. - E7G02

What is ringing in a filter?

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

38. - E7H02

What is a microphonic?

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

39. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all its harmonics?

Select	Answer
A	A cosine wave
B	A sine wave
C	A sawtooth wave
D	A square wave

40. - E8B11

What is digital time division multiplexing?

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

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

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

42. - E8D08

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

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

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	300 watts
B	2000 watts
C	317 watts
D	126 watts

44. - E9B08

What is the far field of an antenna?

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

45. - E9C05

Which of the following is a type of OCFD antenna?

Select	Answer
A	A remotely tunable dipole antenna using orthogonally controlled frequency diversity
B	A multiband dipole antenna using one-way circular polarization for frequency diversity
C	A dipole fed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
D	A folded dipole center-fed with 300-ohm transmission line

46. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Greater structural strength
B	Improved radiation efficiency
C	Higher losses
D	Lower Q

47. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The omega match
B	The gamma match
C	The stub match
D	The delta match

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	7.0 meters
B	8.5 meters
C	10.6 meters
D	13.3 meters

49. - E9G02

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

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

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 utilizing high impedance wire for the coupling loop
C	By winding adjacent turns in opposing directions
D	By increasing the number of turns and/or the area

Figure E6-1

Figure E7-1