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

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1. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

SelectAnswer
AEnsure signals from your station are less than the controlled Maximum Permitted Exposure (MPE) limits
BEnsure signals from your station are less than the uncontrolled Maximum Permitted Exposure (MPE) limits
CEnsure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits
DEnsure signals from your station are less than the uncontrolled Maximum Permitted Emission (MPE) limits

2. - E1A14

Except in some parts of Alaska, what is the maximum power permitted on the 630 meter band?

SelectAnswer
A1 watt EIRP
B50 watts PEP
C5 watts EIRP
D100 watts PEP

3. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

SelectAnswer
AThe amateur station must cease operation
BThe amateur station must cease operation on all frequencies below 30 MHz
CThe amateur station must cease operation on all frequencies above 30 MHz
DThe amateur station must avoid transmitting during certain hours on frequencies that cause the interference

4. - E1C01

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

SelectAnswer
A170 Hz
B1.5 kHz
C60 Hz
D2.8 kHz

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

SelectAnswer
AOnly those of General, Advanced or Amateur Extra Class operators
BAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
CAny amateur station, subject to the privileges of the class of operator license held by the control operator
DOnly those of Amateur Extra Class operators

6. - E1E08

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

SelectAnswer
AEmployees of the VE
BFriends of the VE
CRelatives of the VE as listed in the FCC rules
DAll these choices are correct

7. - E1F02

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

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

8. - E2A10

What type of satellite appears to stay in one position in the sky?

SelectAnswer
AHEO
BGeostationary
CGeomagnetic
DLEO

9. - E2B09

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

SelectAnswer
ANo other hardware is needed
BA special notch filter to remove synchronization pulses
CA special front end limiter
DA special IF converter

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

11. - E2D04

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

SelectAnswer
ADoppler shift of beacon signals
BUltrasonics
CAPRS
DBandwidth compressed LORAN

12. - E2E03

How is the timing of FT4 contacts organized?

SelectAnswer
AIt depends on the lunar phase
BStations take turns on alternate days
CAlternating transmissions at 7.5 second intervals
DBy exchanging ACK/NAK packets

13. - E3A06

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

SelectAnswer
ASwitch to a higher frequency HF band
BSwitch to a lower frequency HF band
CWait 24 hours before attempting another communication on the band
DWait 90 minutes or so for the signal degradation to pass

14. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
APropagation away from the great circle bearing between stations
BSuccessive ionospheric refractions without an intermediate reflection from the ground
CPropagation across the geomagnetic equator
DSignals reflected back toward the transmitting station

15. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the sun will cause disturbed conditions?

SelectAnswer
ASouthward
BNorthward
CWestward
DEastward

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ANetwork analyzer
BModulation monitor
CBit error rate tester
DLogic analyzer

17. - E4B03

Which S parameter is equivalent to forward gain?

SelectAnswer
AS22
BS11
CS12
DS21

18. - E4C03

What is the term for the suppression in an FM receiver of one signal by another stronger signal on the same frequency?

SelectAnswer
ACapture effect
BCross-modulation interference
CDesensitization
DFrequency discrimination

19. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

SelectAnswer
ACross-modulation interference
BQuieting
CDesensitization
DSquelch gain rollback

20. - E4E06

What is one type of electrical interference that might be caused by a nearby personal computer?

SelectAnswer
AA clicking noise at intervals of a few seconds
BA loud AC hum in the audio output of your station receiver
CThe appearance of unstable modulated or unmodulated signals at specific frequencies
DA whining type noise that continually pulses off and on

21. - E5A11

What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

SelectAnswer
A47.3 kHz
B23.67 kHz
C157.8 Hz
D315.6 Hz

22. - E5B05

What happens to the magnitude of a pure reactance when it is converted to a susceptance?

SelectAnswer
AThe sign is reversed
BIt is shifted by 90 degrees
CIt becomes the reciprocal
DIt is unchanged

23. - E5C03

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

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

24. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

SelectAnswer
ATo increase the thermal time constant
BAll these choices are correct
CTo maintain component lifetime
DTo avoid unwanted inductive reactance

25. - E6A09

What is a depletion-mode FET?

SelectAnswer
AAny FET without a channel
BAn FET that exhibits a current flow between source and drain when no gate voltage is applied
CAn FET that has no current flow between source and drain when no gate voltage is applied
DAny FET for which holes are the majority carriers

26. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch?

SelectAnswer
AExtremely high reverse breakdown voltage
BReverse bias controls its forward voltage drop
CAbility to dissipate large amounts of power
DLow junction capacitance

27. - E6C07

What best describes a pull-up or pull-down resistor?

SelectAnswer
AA resistor connected to an op-amp output that prevents signals from exceeding the power supply voltage
BA resistor that ensures that an oscillator frequency does not drift
CA resistor in a keying circuit used to reduce key clicks
DA resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

28. - E6D12

What is inductor saturation?

SelectAnswer
AAdjacent inductors become over-coupled
BThe inductor's voltage rating is exceeded causing a flashover
CThe ability of the inductor's core to store magnetic energy has been exceeded
DThe inductor windings are over-coupled

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

SelectAnswer
AToo many pins
BUnsuitable for combining analog and digital signals
CExcessive lead length
DEpoxy coating is conductive above 300 MHz

30. - E6F09

What is the efficiency of a photovoltaic cell?

SelectAnswer
AThe open-circuit voltage divided by the short-circuit current under full illumination
BThe output RF power divided by the input DC power
CThe relative fraction of light that is converted to current
DCost per kilowatt-hour generated

31. - E7A05

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

SelectAnswer
AJ-K flip-flop
BT flip-flop
CAstable multivibrator
DMonostable multivibrator

32. - E7B12

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

SelectAnswer
ACommon collector
BCommon base
CEmitter follower
DCommon emitter

33. - E7C03

What advantage does a series-L Pi-L-network have over a series-L Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
AHigher efficiency
BGreater harmonic suppression
CGreater transformation range
DDoes not require a capacitor

34. - E7D04

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

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

35. - E7E02

What is the function of a reactance modulator?

SelectAnswer
ATo produce AM signals by using an electrically variable inductance or capacitance
BTo produce PM or FM signals by using an electrically variable inductance or capacitance
CTo produce AM signals by using an electrically variable resistance
DTo produce PM signals by using an electrically variable resistance

36. - E7F02

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

SelectAnswer
AA phase-inverting filter
BA crystal-lattice filter
CA Hilbert-transform filter
DAn adaptive filter

37. - E7G04

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

SelectAnswer
AThe output voltage of the op-amp minus its input voltage
BThe potential between the amplifier input terminals of the op-amp in an open loop condition
CThe difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
DThe differential input voltage needed to bring the open loop output voltage to zero

38. - E7H14

What is a phase-locked loop circuit?

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

39. - E8A04

What is "dither" with respect to analog-to-digital converters?

SelectAnswer
AAn abnormal condition where the converter cannot settle on a value to represent the signal
BAn error caused by irregular quantization step size
CA small amount of noise added to the input signal to allow more precise representation of a signal over time
DA method of decimation by randomly skipping samples

40. - 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?

SelectAnswer
A6000
B3
C2000
D1/3

41. - E8C08

How does ARQ accomplish error correction?

SelectAnswer
ASpecial binary codes provide automatic correction
BIf errors are detected, a retransmission is requested
CSpecial polynomial codes provide automatic correction
DIf errors are detected, redundant data is substituted

42. - E8D05

What is the most common method of reducing key clicks?

SelectAnswer
AIncrease keying waveform rise and fall times
BLow-pass filters at the transmitter output
CReduce keying waveform rise and fall times
DHigh-pass filters at the transmitter output

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

SelectAnswer
A63.2 watts
B252 watts
C632 watts
D159 watts

44. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

SelectAnswer
AThe resulting design will favor radiation of harmonic energy
BThe computed feed point impedance may be incorrect
CGround conductivity will not be accurately modeled
DThe antenna will become mechanically unstable

45. - E9C09

Which of the following describes a G5RV antenna?

SelectAnswer
AA multi-band trap antenna
BA phased array antenna consisting of multiple loops
CA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
DA wide band dipole using shorted coaxial cable for the radiating elements and fed with aÿ4:1 balun

46. - E9D12

Which of the following would provide the best RF ground for your station?

SelectAnswer
AAn electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
BA 50-ohm resistor connected to ground
CAn electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
DAn electrically short connection to a metal water pipe

47. - E9E08

What is a use for a Wilkinson divider?

SelectAnswer
AIt is used to divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance
BIt is used to feed low-impedance loads from a high-impedance source
CIt is used to feed high-impedance antennas from a low-impedance source
DIt divides the operating frequency of a transmitter signal so it can be used on a lower frequency band

48. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

SelectAnswer
AThe characteristic impedance is higher in a parallel feed line
BElectrical signals move more slowly in a coaxial cable than in air
CThe surge impedance is higher in a parallel feed line
DSkin effect is less pronounced in the coaxial cable

49. - E9G05

Which of the following is a common use for a Smith chart?

SelectAnswer
ADetermine the length and position of an impedance matching stub
BDetermine the loss/100 feet of a transmission line, given the velocity factor and conductor materials
CDetermine the impedance of a transmission line, given the physical dimensions
DDetermine the gain of an antenna given the physical and electrical parameters

50. - E9H02

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

SelectAnswer
ALow loss coax transmission line is essential for good performance
BThey must be erected at least 1/2 wavelength above the ground to attain good directivity
CAtmospheric noise is so high that gain over a dipole is not important
DAll these choices are correct

Figure E7-1