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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
B30 to 300 MHz
C300 kHz to 3 MHz
D300 to 3000 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 center frequency of the channel
BOn any frequency where the signal's sidebands are within the channel
CAt the highest frequency of the channel
DAt the lowest frequency of the channel

3. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

SelectAnswer
A30 miles
B10 miles
C1 mile
D3 miles

4. - E1C14

How long must an operator wait after filing a notification with the Utilities Technology Council (UTC) before operating on the 2200 meter or 630 meter band?

SelectAnswer
AOperators may not operate until a test signal has been transmitted in coordination with the local power company
BOperators must not operate until approval is received
COperators may operate after 30 days, providing they have not been told that their station is within 1 km of PLC systems using those frequencies
DOperations may commence immediately, and may continue unless interference is reported by the UTC

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

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

7. - 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?

SelectAnswer
AIt must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
BIt must exhibit a gain of 0 dB or less over its full output range
CIt must produce full legal output when driven by not more than 5 watts of mean RF input power
DIt must be capable of external RF switching between its input and output networks

8. - E2A02

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

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

9. - E2B12

What signals SSTV receiving software to begin a new picture line?

SelectAnswer
AElapsed time
BA two-tone signal
CSpecific tone frequencies
DSpecific tone amplitudes

10. - E2C09

What type of equipment is commonly used to implement an amateur radio mesh network?

SelectAnswer
AA wireless router running custom firmware
BA 440 MHz transceiver with a 9600 baud modem
CAn optical cable connection between the USB ports of 2 separate computers
DA 2 meter VHF transceiver with a 1200 baud modem

11. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
ADisconnect
BUnnumbered Information
CAcknowledgement
DConnect

12. - E2E07

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

SelectAnswer
AThe protocol version you are using is not supported by the digital station
BYour transmit frequency is incorrect
CAll these choices are correct
DAnother station you are unable to hear is using the frequency

13. - E3A14

What is meant by circularly polarized electromagnetic waves?

SelectAnswer
AWaves produced by a loop antenna
BWaves with an electric field bent into a circular shape
CWaves that circle the Earth
DWaves with a rotating electric field

14. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A2500 miles
B7500 miles
C5000 miles
D1000 miles

15. - E3C01

What does the radio communication term "ray tracing" describe?

SelectAnswer
AThe process in which an electronic display presents a pattern
BModeling a radio wave's path through the ionosphere
CDetermining the radiation pattern from an array of antennas
DEvaluating high voltage sources for x-rays

16. - E4A03

Which of the following test instruments is used to display spurious signals and/or intermodulation distortion products generated by an SSB transmitter?

SelectAnswer
AA spectrum analyzer
BA wattmeter
CA time-domain reflectometer
DA logic analyzer

17. - E4B04

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

SelectAnswer
AS12
BS22
CS21
DS11

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

SelectAnswer
AMultiple frequencies can be received simultaneously if desired
BReceiver power consumption can be reduced when wider bandwidth is not required
CReceive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference
DThe noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity

19. - E4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

SelectAnswer
AOscillator instability and severe audio distortion of all but the strongest received signals
BOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
CSpurious signals caused by cross-modulation and desensitization from strong adjacent signals
DCross-modulation of the desired signal and insufficient audio power to operate the speaker

20. - E4E05

How can radio frequency interference from an AC motor be suppressed?

SelectAnswer
ABy installing a brute-force AC-line filter in series with the motor leads
BBy installing a high-pass filter in series with the motor's power leads
CBy installing a bypass capacitor in series with the motor leads
DBy using a ground-fault current interrupter in the circuit used to power the motor

21. - E5A02

What is resonance in an LC or RLC circuit?

SelectAnswer
AThe frequency at which the capacitive reactance equals the inductive reactance
BThe highest frequency that will pass current
CThe frequency at which the reactive impedance equals the resistive impedance
DThe lowest frequency that will pass current

22. - E5B03

How is impedance in polar form converted to an equivalent admittance?

SelectAnswer
ATake the reciprocal of the angle and change the sign of the magnitude
BSquare the magnitude and subtract 90 degrees from the angle
CTake the square root of the magnitude and add 180 degrees to the angle
DTake the reciprocal of the magnitude and change the sign of the angle

23. - E5C06

What does the impedance 50-j25 represent?

SelectAnswer
A25 ohms resistance in series with 50 ohms inductive reactance
B50 ohms resistance in series with 25 ohms capacitive reactance
C50 ohms resistance in series with 25 ohms inductive reactance
D25 ohms resistance in series with 50 ohms capacitive reactance

24. - E5D14

What is reactive power?

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

25. - E6A10

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

SelectAnswer
A6
B2
C4
D5

26. - E6B03

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

SelectAnswer
AReverse bias
BZero bias
CForward bias
DInductive bias

27. - E6C02

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

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

28. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

SelectAnswer
AToroidal cores have lower Q characteristics
BToroidal cores confine most of the magnetic field within the core material
CToroidal cores exhibit greater hysteresis
DToroidal cores make it easier to couple the magnetic energy into other components

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
CGallium nitride
DSilicon

30. - E6F06

Which of these materials is most commonly used to create photoconductive devices?

SelectAnswer
AAn ordinary metal
BA heavy metal
CA liquid semiconductor
DA crystalline semiconductor

31. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
ANegative logic
BAssertive Logic
CPositive Logic
DReverse Logic

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

SelectAnswer
ALow input impedance
BLow bandwidth
CHigh power gain
DHigh filament voltage

33. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with extreme stop band ripple
BExtremely flat response over its pass band with gradually rounded stop band corners
CExtremely sharp cutoff with one or more notches in the stop band
DGradual passband rolloff with minimal stop band ripple

34. - E7D05

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

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

35. - E7E10

How does a diode envelope detector function?

SelectAnswer
ABy breakdown of the Zener voltage
BBy mixing signals with noise in the transition region of the diode
CBy rectification and filtering of RF signals
DBy sensing the change of reactance in the diode with respect to frequency

36. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

SelectAnswer
AAn elliptical filter
BA Hilbert-transform filter
CAn adaptive filter
DA notch filter

37. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A14
B7
C0.07
D28

38. - E7H15

Which of these functions can be performed by a phase-locked loop?

SelectAnswer
APhotovoltaic conversion, optical coupling
BFrequency synthesis, FM demodulation
CWide-band AF and RF power amplification
DComparison of two digital input signals, digital pulse counter

39. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

SelectAnswer
A1 to 1
B2.5 to 1
C25 to 1
D100 to 1

40. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AOFDM signals are not allowed on amateur bands
BExtremely low-power contacts
CHigh-speed digital modes
DEME

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A5.76 kHz
B4.8 kHz
C9.6 kHz
D15.36 kHz

42. - E8D06

What is the advantage of including parity bits in ASCII characters?

SelectAnswer
AForeign language characters can be sent
BSome types of errors can be detected
CFaster transmission rate
DThe signal can overpower interfering signals

43. - E9A10

Which of the following improves the efficiency of a ground-mounted quarter-wave vertical antenna?

SelectAnswer
AIsolating the coax shield from ground
BInstalling a radial system
CAll these choices are correct
DShortening the radiating element

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

SelectAnswer
A38 dB
B28 dB
C3 dB
D15 dB

45. - E9C06

What is the effect of adding a terminating resistor to a rhombic antenna?

SelectAnswer
AIt changes the radiation pattern from bidirectional to unidirectional
BIt changes the radiation pattern from horizontal to vertical polarization
CIt decreases the ground loss
DIt reflects the standing waves on the antenna elements back to the transmitter

46. - E9D05

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

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

47. - E9E05

How must an antenna's driven element be tuned to use a hairpin matching system?

SelectAnswer
AThe driven element radiation resistance must be higher than the characteristic impedance of the transmission line
BThe driven element reactance must be inductive
CThe driven element resonance must be lower than the operating frequency
DThe driven element reactance must be capacitive

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
C13.3 meters
D8.5 meters

49. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

SelectAnswer
ACoaxial-length circles
BAntenna-length circles
CRadiation-pattern circles
DStanding wave ratio circles

50. - E9H02

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

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

Figure E6-1

Figure E7-3