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

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1. - E0A03

Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

SelectAnswer
A300 kHz to 3 MHz
B3 to 30 MHz
C300 to 3000 MHz
D30 to 300 MHz

2. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

SelectAnswer
AAt the highest frequency of the channel
BAt the lowest frequency of the channel
CAt the center frequency of the channel
DOn any frequency where the signal's sidebands are within the channel

3. - E1B11

What does PRB-1 require of regulations affecting amateur radio?

SelectAnswer
AReasonable accommodations of amateur radio must be made
BAmateur radio operations must be permitted in any private residence
CUse of wireless devices in a vehicle is exempt from regulation
DNo limitations may be placed on antenna size or placement

4. - E1C09

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

SelectAnswer
A3.0
B2.0
C1.0
D0.5

5. - E1D06

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

SelectAnswer
A1 watt
B100 watts
C2 watts
D5 watts

6. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

SelectAnswer
AEach administering VE
BThe VEC coordinating the session
CThe VE session manager
DThe FCC

7. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the government of Canada?

SelectAnswer
ANone, they must obtain a U.S. license
BFull privileges, up to and including those of the Amateur Extra Class license, on the 80, 40, 20, 15, and 10 meter bands
CThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Amateur Extra Class license privileges
DAll privileges of the Amateur Extra Class license

8. - E2A01

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

SelectAnswer
AFrom south to north
BFrom east to west
CFrom west to east
DFrom north to south

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

SelectAnswer
AUsing converted satellite TV dishes
BTransmitting on the abandoned TV channel 2
CTransmitting on channels shared with cable TV
DUsing USB and demodulating the signal with a computer sound card

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.?

SelectAnswer
A/R# where # is the district of the remote station
B/ followed by the ARRL Section of the remote station
C/ followed by the USPS two-letter abbreviation for the state in which the remote station is located
DNo additional indicator is required

11. - E2D07

What digital protocol is used by APRS?

SelectAnswer
A802.11
BPACTOR
CAX.25
DAMTOR

12. - E2E03

How is the timing of FT4 contacts organized?

SelectAnswer
ABy exchanging ACK/NAK packets
BAlternating transmissions at 7.5 second intervals
CIt depends on the lunar phase
DStations take turns on alternate days

13. - E3A02

What characterizes libration fading of an EME signal?

SelectAnswer
AA gradual loss of signal as the sun rises
BThe returning echo is several hertz lower in frequency than the transmitted signal
CA slow change in the pitch of the CW signal
DA fluttery irregular fading

14. - E3B09

At what time of year is sporadic E propagation most likely to occur?

SelectAnswer
AAround the equinoxes, especially the fall equinox
BAround the solstices, especially the winter solstice
CAround the solstices, especially the summer solstice
DAround the equinoxes, especially the spring equinox

15. - E3C02

What is indicated by a rising A or K index?

SelectAnswer
AIncreasing disruption of the geomagnetic field
BAn increase in the critical frequency
CHigher levels of solar UV radiation
DDecreasing disruption of the geomagnetic field

16. - E4A08

Which of the following measures SWR?

SelectAnswer
AAn antenna analyzer
BA Q meter
CA spectrum analyzer
DAn ohmmeter

17. - E4B11

Which of the following can be measured with a vector network analyzer?

SelectAnswer
AAll these choices are correct
BReflection coefficient
COutput impedance
DInput impedance

18. - E4C04

What is the noise figure of a receiver?

SelectAnswer
AThe ratio of thermal noise to atmospheric noise
BThe ratio in dB of the noise generated by the receiver to the theoretical minimum noise
CThe ratio of the noise bandwidth in hertz to the theoretical bandwidth of a resistive network
DThe ratio of atmospheric noise to phase noise

19. - E4D06

What is the term for spurious signals generated by the combination of two or more signals in a non-linear device or circuit?

SelectAnswer
AAdjacent channel interference
BNeutralization
CIntermodulation
DAmplifier desensitization

20. - E4E07

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
ALow inductance ground connections at both ends of the shield
BUse of braided shielding material
CTying all ground connections to a common point resulting in differential-mode currents in the shield
DCommon-mode currents on the shield and conductors

21. - E5A08

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

SelectAnswer
AThe voltage leads the current by 90 degrees
BThe voltage and current are 180 degrees out of phase
CThe voltage and current are in phase
DThe current leads the voltage by 90 degrees

22. - E5B10

What is the relationship between the AC current through an inductor and the voltage across an inductor?

SelectAnswer
AVoltage and current are in phase
BVoltage and current are 180 degrees out of phase
CVoltage leads current by 90 degrees
DCurrent leads voltage by 90 degrees

23. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

SelectAnswer
AA positive magnitude
BA negative phase angle
CA positive phase angle
DA negative magnitude

24. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100 VAC at 4 amperes?

SelectAnswer
A400 watts
B80 watts
C2000 watts
D50 watts

25. - E6A11

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

SelectAnswer
A1
B2
C3
D6

26. - E6B01

What is the most useful characteristic of a Zener diode?

SelectAnswer
AA negative resistance region
BAn internal capacitance that varies with the applied voltage
CA constant voltage drop under conditions of varying current
DA constant current drop under conditions of varying voltage

27. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

SelectAnswer
AThe IC input can be damaged
BThe feedback loop becomes unstable
CThe comparator enters latch-up
DThe comparator changes its output state

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

SelectAnswer
AFerrite
BBrass
CPowdered iron
DCeramic

29. - E6E02

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

SelectAnswer
ABall grid array
BDIP
CSOT
DPLCC

30. - E6F01

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

SelectAnswer
AHoles
BProtons
CPhotons
DElectrons

31. - E7A07

What logical operation does a NAND gate perform?

SelectAnswer
AIt produces logic 0 at its output if some but not all inputs are logic 1
BIt produces logic 0 at its output only when all inputs are logic 1
CIt produces logic 1 at its output only when all inputs are logic 1
DIt produces logic 0 at its output only when all inputs are logic 0

32. - E7B03

Which of the following components form the output of a class D amplifier circuit?

SelectAnswer
AA matched load resistor to prevent damage by switching transients
BA high-pass filter to compensate for low gain at low frequencies
CA low-pass filter to remove switching signal components
DA temperature compensating load resistor to improve linearity

33. - E7C07

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50-ohm unbalanced output?

SelectAnswer
AA Phase Inverter Load network
BA network with only three discrete parts
CA matching network in which all components are isolated from ground
DA Pi-network with an additional series inductor on the output

34. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

SelectAnswer
AA shunt current source
BA constant current source
CA series regulator
DA shunt regulator

35. - E7E05

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

SelectAnswer
AA heterodyne enhancer
BA de-emphasis network
CA pre-emphasis network
DA heterodyne suppressor

36. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
ASoftware is converted from source code to object code during operation of the receiver
BA switching mixer is used to generate I and Q signals directly from the RF input
CIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
DIncoming RF is converted to a control voltage for a voltage controlled oscillator

37. - E7G01

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

SelectAnswer
AVery high
B100 ohms
C1000 ohms
DVery low

38. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic circuit consisting of a precision push-pull amplifier with a differential input
BAn electronic circuit also known as a monostable multivibrator
CAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
DAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator

39. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AAll these choices are correct
BImmunity to out-of-sequence coding reduces spurious responses
CVery high speed allows digitizing high frequencies
DVery low power consumption decreases frequency drift

40. - E8B09

What is deviation ratio?

SelectAnswer
AThe ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
BThe ratio of the audio modulating frequency to the center carrier frequency
CThe ratio of the carrier center frequency to the audio modulating frequency
DThe ratio of the highest audio modulating frequency to the average audio modulating frequency

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

SelectAnswer
AModulation index and output power
BKeying speed and shape factor (rise and fall time)
CIF bandwidth and Q
DAll these choices are correct

42. - E8D07

What is a common cause of overmodulation of AFSK signals?

SelectAnswer
AGround loops
BExcessive transmit audio levels
CExcessive numbers of retries
DBit errors in the modem

43. - E9A04

Which of the following factors affect the feed point impedance of an antenna?

SelectAnswer
AThe settings of an antenna tuner at the transmitter
BAntenna height
CThe input power level
DTransmission line length

44. - E9B05

What type of antenna pattern is shown in Figure E9-2?

SelectAnswer
AElevation
BRadiation resistance
CAzimuth
DPolarization

45. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?

SelectAnswer
AThe low-angle radiation increases
BFewer vertical angle lobes will be present
CThe low-angle radiation decreases
DAdditional higher vertical angle lobes will appear

46. - E9D08

What happens as the Q of an antenna increases?

SelectAnswer
AGain is reduced
BMore common-mode current is present on the feed line
CSWR bandwidth decreases
DSWR bandwidth increases

47. - E9E09

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

SelectAnswer
AHairpin match
BGamma match
CDouble-bazooka match
DAll these choices are correct

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?

SelectAnswer
A10.6 meters
B7.0 meters
C8.5 meters
D13.3 meters

49. - E9G02

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

SelectAnswer
AVoltage circles and current arcs
BResistance lines and reactance chords
CVoltage lines and current chords
DResistance circles and reactance arcs

50. - E9H09

What is a Pennant antenna?

SelectAnswer
AA stealth antenna built to look like a flagpole
BA four-element, high-gain vertical array invented by George Pennant
CA small, vertically oriented receiving antenna consisting of a triangular loop terminated in approximately 900 ohms
DA form of rhombic antenna terminated in a variable capacitor to provide frequency diversity

Figure E6-1

Figure E9-2