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

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1. - E1A14

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

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

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	No special rules apply if your antenna structure will be less than 300 feet in height
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 FCC rules
D	You must obtain a construction permit from the airport zoning authority

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. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
B	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
C	An amateur station located more than 50 km above the Earth's surface
D	An amateur station that transmits telemetry consisting of measurements of upper atmosphere

5. - E1E08

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

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

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must exhibit a gain of 0 dB or less over its full output range
B	It must produce full legal output when driven by not more than 5 watts of mean RF input power
C	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
D	It must be capable of external RF switching between its input and output networks

7. - E2A01

What is the direction of an ascending pass for an amateur satellite?

Select	Answer
A	From north to south
B	From east to west
C	From west to east
D	From south to north

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Spectral Intensity
B	Chroma
C	Luminance
D	Hue

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To separate the calling stations from the DX station
B	All of these choices are correct
C	To improve operating efficiency by reducing interference
D	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

Select	Answer
A	170 Hz shift, 45 baud RTTY
B	PSK31
C	AMTOR
D	300 baud packet

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	The protocol version you are using is not the supported by the digital station
B	Another station you are unable to hear is using the frequency
C	Your transmit frequency is incorrect
D	All of these choices are correct

12. - E3A04

What do Hepburn maps predict?

Select	Answer
A	Likelihood of rain-scatter along cold or warm fronts
B	Probability of tropospheric propagation
C	Sporadic E propagation
D	Locations of auroral reflecting zones

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Afternoon or early evening
B	Morning
C	Noon
D	Late at night

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
B	The solar emission at 304 GHz, correlated to X-Ray flare levels
C	The ratio of X-Ray flux to radio flux, correlated to sunspot number
D	UV emissions at 304 angstroms, correlated to solar flux index

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Analog-to-digital conversion speed of the soundcard
B	Q of the interface of the interface circuit
C	All of these choices are correct
D	Amount of memory on the soundcard

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High impedance input
B	High reluctance input
C	Low reluctance input
D	Low impedance input

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	-174 dBm
C	-155 dBm
D	-148 dBm

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	The off-frequency unwanted signal is heard in addition to the desired signal
B	A reduction in apparent signal strength
C	A large increase in background noise
D	The desired signal can no longer be heard

19. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals which have a sharply peaked frequency distribution
B	Signals which appear at one IF but not another
C	Signals which are constant at all IF levels
D	Signals which appear across a wide bandwidth

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

Select	Answer
A	Reactance of either the inductance or capacitance multiplied by the resistance
B	Reactance of the inductance multiplied by the reactance of the capacitance
C	Reactance of either the inductance or capacitance divided by the resistance
D	Resistance divided by the reactance of either the inductance or capacitance

21. - E5B03

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

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

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 1
B	Point 5
C	Point 3
D	Point 8

23. - E5D14

What is reactive power?

Select	Answer
A	Power lost because of capacitor leakage
B	Power consumed in circuit Q
C	Wattless, nonproductive power
D	Power consumed in wire resistance in an inductor

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to base current
B	The change of collector current with respect to emitter current
C	The change of collector current with respect to gate current
D	The change of base current with respect to collector current

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Zero bias
B	Inductive bias
C	Forward bias
D	Reverse bias

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	High speed operation
B	More efficient arithmetic operations
C	Ability to connect many device outputs to a common bus
D	Low power consumption

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

Select	Answer
A	From approximately 10 Hz to no more than 3000 kHz
B	From less than 20 Hz to approximately 300 MHz
C	From about 100 kHz to at least 1000 GHz
D	From a few kHz to no more than 30 MHz

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
B	Two chips in each package (Dual In Package)
C	Package mounts in a direct inverted position
D	Low leakage doubly insulated package

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	An LED and a phototransistor
B	A lens and a photomultiplier
C	A frequency modulated helium-neon laser
D	An amplitude modulated helium-neon laser

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	A flip-flop
B	A clock
C	An "OR" gate
D	An "AND" gate

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

Select	Answer
A	The entire cycle
B	Exactly 180 degrees
C	Less than 180 degrees
D	More than 180 degrees but less than 360 degrees

32. - E7C13

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	The Q of Pi-networks can be varied depending on the component values chosen
B	Pi-networks have fewer components
C	L-networks cannot perform impedance transformation
D	Pi-networks are designed for balanced input and output

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To allow the filter capacitors to charge gradually
B	To allow for remote control of the power supply
C	To provide a dual-voltage output for reduced power applications
D	To compensate for variations of the incoming line voltage

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By driving a product detector with a DSB signal
B	By using a balanced modulator followed by a filter
C	By using a loop modulator followed by a mixer
D	By using a reactance modulator followed by a mixer

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters delay all frequency components of the signal by the same amount
B	FIR filters are easier to implement for a given set of passband rolloff requirements
C	All of these choices are correct
D	FIR filters can respond faster to impulses

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a capacitive divider
C	Through link coupling
D	Through a tapped coil

38. - E8A03

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

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

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal jumps from band to band at a predetermined rate
B	The transmitted signal is divided into packets of information
C	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
D	Two or more information streams are merged into a baseband, which then modulates the transmitter

40. - E8C08

How does ARQ accomplish error correction?

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

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	High-pass filters at the transmitter output
B	Reduce keying waveform rise and fall times
C	Low-pass filters at the transmitter output
D	Increase keying waveform rise and fall times

42. - E9A18

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

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

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of segments, each having a distinct value of voltage across it
B	A wire is modeled as a series of segments, each having a uniform value of current
C	A wire is modeled as a single sine-wave current generator
D	A wire is modeled as a series of points, each having a distinct location in space

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

45. - E9D08

What happens as the Q of an antenna increases?

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

46. - E9E13

What is a use for a Wilkinson divider?

Select	Answer
A	It is used to feed low-impedance loads from a high-impedance source
B	It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedance
C	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
D	It is used to feed high-impedance antennas from a low-impedance source

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	6.9 meters
B	24 meters
C	10 meters
D	50 meters

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Reactance and voltage
B	Resistance and reactance
C	Resistance and voltage
D	Voltage and impedance

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
B	It narrows the bandwidth of the received signal to improve signal to noise ratio
C	It compensates for the effects of an isotropic antenna, thereby improving directivity
D	It prevents receiver overload which could make it difficult to determine peaks or nulls

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Reduce RFI to telephones and home entertainment systems
B	Lightning protection
C	Reduce RF current flow between pieces of equipment
D	Reduce received noise

Figure E5-2