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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
A3 to 30 MHz
B300 to 3000 MHz
C30 to 300 MHz
D300 kHz to 3 MHz

2. - E1A07

What is the maximum power permitted on the 2200 meter band?

SelectAnswer
A50 watts PEP
B1 watt EIRP (Equivalent isotropic radiated power)
C5 watts EIRP (Equivalent isotropic radiated power)
D100 watts PEP

3. - 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?

SelectAnswer
AYou must obtain a construction permit from the airport zoning authority
BYou must submit engineering drawings to the FAA
CYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules
DYou must file an Environmental Impact Statement with the EPA before construction begins

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

SelectAnswer
AA special endorsement must be requested from the FCC
BAn environmental impact statement must be filed with the Department of the Interior
COperators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
DOperators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station

5. - E1D03

What is a space telecommand station?

SelectAnswer
AAn amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites
BAn amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth
CAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
DAn amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth

6. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

SelectAnswer
AAll these choices are correct
BThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
CPhotocopy all examination documents and forward them to the FCC for processing
DIssue the examinee the new or upgrade license

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. - E2A02

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

SelectAnswer
ADoppler shift is reduced because the uplink and downlink shifts are in opposite directions
BUpper sideband on the uplink becomes lower sideband on the downlink, and vice versa
CSignal position in the band is reversed
DAll these choices are correct

9. - E2B10

What aspect of an analog slow-scan television signal encodes the brightness of the picture?

SelectAnswer
ASync frequency
BTone amplitude
CSync amplitude
DTone frequency

10. - E2C07

What is the Cabrillo format?

SelectAnswer
AA method of exchanging information during a contest QSO
BThe most common set of contest rules
CThe rules of order for meetings between contest sponsors
DA standard for submission of electronic contest logs

11. - E2D05

What is one advantage of the JT65 mode?

SelectAnswer
APermits fast-scan TV transmissions over narrow bandwidth
BUses only a 65 Hz bandwidth
CThe ability to decode signals which have a very low signal-to-noise ratio
DEasily copied by ear if necessary

12. - E2E09

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

SelectAnswer
ARTTY
BPACTOR
CMT63
DPSK31

13. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by EME?

SelectAnswer
A5000 miles, if the moon is at perigee
B12,000 miles, if the moon is visible by both stations
C500 miles, if the moon is at perigee
D2000 miles, if the moon is at apogee

14. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between points at the same latitude
BPropagation between a point on the equator and its antipodal point
CPropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
DPropagation between points located on the magnetic equator

15. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

SelectAnswer
AClass A
BClass B
CClass M
DClass X

16. - E4A11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

SelectAnswer
ALoosely couple the antenna and a dummy load to the analyzer
BLoosely couple the analyzer near the antenna base
CConnect the analyzer via a high-impedance transformer to the antenna
DConnect the antenna feed line directly to the analyzer's connector

17. - E4B04

Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

SelectAnswer
AS12
BS11
CS21
DS22

18. - E4C04

What is the noise figure of a receiver?

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

19. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

SelectAnswer
AA properly terminated circulator at the output of the repeater's transmitter
BA band-pass filter in the feed line between the transmitter and receiver
CUtilizing a Class D final amplifier
DUtilizing a Class C final amplifier

20. - E4E01

What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals?

SelectAnswer
ARemoval of the CW signal as well as the interfering carrier
BAny nearby signal passing through the DSP system will overwhelm the desired signal
CReceived CW signals will appear to be modulated at the DSP clock frequency
DRinging in the DSP filter will completely remove the spaces between the CW characters

21. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

SelectAnswer
AApproximately equal to circuit resistance
BHigh, as compared to the circuit resistance
CApproximately equal to inductive reactance
DApproximately equal to capacitive reactance

22. - E5B06

What is susceptance?

SelectAnswer
AThe imaginary part of admittance
BThe ratio of magnetic field to electric field
CThe magnetic impedance of a circuit
DA measure of the efficiency of a transformer

23. - E5C03

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

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

24. - E5D14

What is reactive power?

SelectAnswer
AWattless, nonproductive power
BPower consumed in wire resistance in an inductor
CPower lost because of capacitor leakage
DPower consumed in circuit Q

25. - E6A02

Which of the following semiconductor materials contains excess free electrons?

SelectAnswer
AInsulated gate
BN-type
CP-type
DBipolar

26. - E6B05

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

SelectAnswer
AAbility to dissipate large amounts of power
BExtremely high reverse breakdown voltage
CReverse bias controls its forward voltage drop
DLow junction capacitance

27. - E6C02

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

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

28. - E6D12

What is inductor saturation?

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

29. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

SelectAnswer
ASilicon dioxide
BSilicon nitride
CSilicon
DGallium nitride

30. - E6F05

Which describes an optical shaft encoder?

SelectAnswer
AA digital encryption device often used to encrypt spacecraft control signals
BA device that detects rotation of a control by interrupting a light source with a patterned wheel
CA device for generating RTTY signals by means of a rotating light source
DA device that measures the strength of a beam of light using analog to digital conversion

31. - E7A08

What logical operation does an OR gate perform?

SelectAnswer
AIt produces logic 1 at its output if all inputs are logic 0
BIt only produces logic 0 at its output when all inputs are logic 1
CIt produces logic 1 at its output if any or all inputs are logic 1
DIt produces logic 0 at its output if all inputs are logic 1

32. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

SelectAnswer
AThe tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
BThe loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
CThe tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
DThe loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current

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
AGreater transformation range
BHigher efficiency
CGreater harmonic suppression
DDoes not require a capacitor

34. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-2?

SelectAnswer
AIt is a brute force filter for the output
BTo self-resonate at the hum frequency
CIt bypasses rectifier output ripple around D1
DTo provide fixed DC bias for Q1

35. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
AFor compatibility with transmitters using phase modulation
BTo reduce impulse noise reception
CTo remove third-order distortion products
DFor higher efficiency

36. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

SelectAnswer
AVarying quartz crystal characteristics emulated in digital form
BMixing products are converted to voltages and subtracted by adder circuits
CA frequency synthesizer removes the unwanted sidebands
DSignals are combined in quadrature phase relationship

37. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt does not vary with frequency
BIt decreases linearly with increasing frequency
CIt increases linearly with increasing frequency
DIt decreases logarithmically with increasing frequency

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

SelectAnswer
ATaft, Pierce and negative feedback
BTaft, Hartley and Pierce
CColpitts, Hartley and Pierce
DPierce, Fenner and Beane

39. - E8A09

How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

SelectAnswer
A8 multiplied by the gain of the input amplifier
B8
C256 divided by the gain of the input amplifier
D256

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
A2000
B1/3
C3
D6000

41. - E8C04

What technique minimizes the bandwidth of a PSK31 signal?

SelectAnswer
AZero-sum character encoding
BUse of sinusoidal data pulses
CUse of trapezoidal data pulses
DReed-Solomon character encoding

42. - E8D01

Why are received spread spectrum signals resistant to interference?

SelectAnswer
ASignals not using the spread spectrum algorithm are suppressed in the receiver
BIf interference is detected by the receiver it will signal the transmitter to change frequencies
CThe receiver is always equipped with a digital blanker
DThe high power used by a spread spectrum transmitter keeps its signal from being easily overpowered

43. - E9A03

What is the radiation resistance of an antenna?

SelectAnswer
AThe resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
BThe combined losses of the antenna elements and feed line
CThe specific impedance of the antenna
DThe value of a resistance that would dissipate the same amount of power as that radiated from an antenna

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

SelectAnswer
A50 degrees
B75 degrees
C25 degrees
D30 degrees

45. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

SelectAnswer
A300 ohms
B72 ohms
C450 ohms
D50 ohms

46. - E9D05

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

SelectAnswer
AThe front-to-back ratio increases
BThe front-to-back ratio decreases
CThe SWR is reduced
DThe frequency response is widened over the whole frequency band

47. - E9E09

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

SelectAnswer
ADouble-bazooka match
BAll these choices are correct
CHairpin match
DGamma match

48. - E9F04

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

SelectAnswer
AThe same as the output impedance of the generator
BThe same as the characteristic impedance of the line
CVery high impedance
DVery low impedance

49. - E9G01

Which of the following can be calculated using a Smith chart?

SelectAnswer
ARadiation resistance
BRadio propagation
CImpedance along transmission lines
DAntenna radiation pattern

50. - E9H07

Why is RF attenuation used when direction-finding?

SelectAnswer
ATo increase receiver sensitivity
BTo compensate for isotropic directivity and the antenna effect of feed lines
CTo prevent receiver overload which reduces pattern nulls
DTo narrow the receiver bandwidth

Figure E7-2

Figure E9-1