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

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1. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

SelectAnswer
AMica
BBeryllium Oxide
CUranium Hexafluoride
DZinc oxide

2. - E1A09

What action or actions should you take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

SelectAnswer
AAll these choices are correct
BNotify the nearest FCC Field Engineers office
CDiscontinue forwarding the communication as soon as you become aware of it
DNotify the originating station that the communication does not comply with FCC rules

3. - E1B03

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

SelectAnswer
A3 miles
B1 mile
C30 miles
D10 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
COperations may commence immediately, and may continue unless interference is reported by the UTC
DOperators may operate after 30 days, providing they have not been told that their station is within 1 km of PLC systems using those frequencies

5. - E1D03

What is a space telecommand station?

SelectAnswer
AAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
BAn amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
CAn amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites
DAn amateur station that receives telemetry from a satellite or 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
APhotocopy all examination documents and forward them to the FCC for processing
BThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
CIssue the examinee the new or upgrade license
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
BFull privileges, up to and including those of the Amateur Extra Class license, on the 80, 40, 20, 15, and 10 meter bands
CNone, they must obtain a U.S. license
DThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Amateur Extra Class license privileges

8. - E2A04

What is meant by the term mode? as applied to an amateur radio satellite?

SelectAnswer
AWhether the satellite is in a low earth or geostationary orbit
BWhether the satellite is in a polar or equatorial orbit
CThe satellite's uplink and downlink frequency bands
DThe satellite's orientation with respect to the Earth

9. - E2B04

How is color information sent in analog SSTV?

SelectAnswer
AColor is amplitude modulated on the frequency modulated intensity signal
BColor information is sent on a 2.8 kHz subcarrier
CColor lines are sent sequentially
DColor is sent in a color burst at the end of each line

10. - E2C09

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

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

11. - E2D09

What type of modulation is used for JT65 contacts?

SelectAnswer
ARTTY
BIEEE 802.11
CMulti-tone AFSK
DPSK

12. - E2E11

What is the difference between direct FSK and audio FSK?

SelectAnswer
ADirect FSK can transmit faster baud rates
BDirect FSK occupies less bandwidth
CDirect FSK applies the data signal to the transmitter VFO, while AFSK transmits tones via phone
DOnly direct FSK can be decoded by computer

13. - E3A02

What characterizes libration fading of an EME signal?

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

14. - E3B11

At what time of day can sporadic E propagation occur?

SelectAnswer
AOnly around sunset and sunrise
BOnly in hours of darkness
CAny time
DOnly around sunset

15. - E3C05

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

SelectAnswer
ASouthward
BEastward
CNorthward
DWestward

16. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

SelectAnswer
AAntenna analyzers do not need an external RF source
BAntenna analyzers automatically tune your antenna for resonance
CAntenna analyzers display a time-varying representation of the modulation envelope
DAll these choices are correct

17. - E4B02

What is the significance of voltmeter sensitivity expressed in ohms per volt?

SelectAnswer
AThe full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
BWhen used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
CWhen used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
DWhen used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test

18. - E4C01

What is an effect of excessive phase noise in a receiver's local oscillator?

SelectAnswer
AIt decreases receiver third-order intercept point
BIt limits the receiver's ability to receive strong signals
CIt can affect the receiver's frequency calibration
DIt can combine with strong signals on nearby frequencies to generate interference

19. - E4D09

What is the purpose of the preselector in a communications receiver?

SelectAnswer
ATo allow selection of the optimum RF amplifier device
BTo provide a range of AGC time constants
CTo increase rejection of signals outside the desired band
DTo store often-used frequencies

20. - E4E03

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

SelectAnswer
ASignals that appear across a wide bandwidth
BSignals that have a sharply peaked frequency distribution
CSignals that are constant at all IF levels
DSignals that appear at one IF but not another

21. - E5A05

What is the result of increasing the Q of an impedance-matching circuit?

SelectAnswer
AIt has no effect on impedance matching
BMatching bandwidth is increased
CMatching range is increased
DMatching bandwidth is decreased

22. - E5B12

What is admittance?

SelectAnswer
AThe turns ratio of a transformer
BThe inverse of impedance
CThe term for the gain of a field effect transistor
DThe inverse of Q factor

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

SelectAnswer
AThe X axis represents the magnitude and the Y axis represents the phase angle
BThe X axis represents the resistive component and the Y axis represents the reactive component
CThe X axis represents the phase angle and the Y axis represents the magnitude
DThe X axis represents the reactive component and the Y axis represents the resistive component

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
B50 watts
C80 watts
D2000 watts

25. - E6A06

What is the beta of a bipolar junction transistor?

SelectAnswer
AThe switching speed
BThe frequency at which the current gain is reduced to 0.707
CThe change in collector current with respect to base current
DThe breakdown voltage of the base to collector junction

26. - E6B08

Which of the following is a Schottky barrier diode?

SelectAnswer
AMetal-semiconductor junction
BPIN junction
CThermionic emission diode
DElectrolytic rectifier

27. - E6C03

What is tri-state logic?

SelectAnswer
ALogic devices that utilize ternary math
BLogic devices with 0, 1, and high-impedance output states
CProprietary logic devices manufactured by Tri-State Devices
DLow-power logic devices designed to operate at 3 volts

28. - E6D01

Why should core saturation of an impedance matching transformer be avoided?

SelectAnswer
ARF susceptance would increase
BMagnetic flux would increase with frequency
CTemporary changes of the core permeability could result
DHarmonics and distortion could result

29. - E6E11

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

SelectAnswer
AA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
BLow leakage doubly insulated package
CPackage mounts in a direct inverted position
DTwo chips in each package (Dual In Package)

30. - E6F06

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

SelectAnswer
AA heavy metal
BAn ordinary metal
CA liquid semiconductor
DA crystalline semiconductor

31. - E7A09

What logical operation is performed by an exclusive NOR gate?

SelectAnswer
AIt produces logic 1 at its output only if all inputs are logic 1
BIt produces logic 0 at its output only if all inputs are logic 0
CIt produces logic 0 at its output if only one input is logic 1
DIt produces logic 1 at its output if only one input is logic 1

32. - E7B11

In Figure E7-1, what is the purpose of R3?

SelectAnswer
AEmitter bypass
BOutput load resistor
CSelf bias
DFixed bias

33. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

SelectAnswer
AIt is a notch filter
BIt is a band-pass filter
CIt is a low-pass filter
DIt is a high-pass filter

34. - E7D10

What is the primary reason that a high-frequency switching type high-voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

SelectAnswer
AIt uses a large power factor compensation capacitor to recover power from the unused portion of the AC cycle
BThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
CThe inverter design does not require any output filtering
DIt uses a diode bridge rectifier for increased output

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

SelectAnswer
AAn automatic band-switching circuit
BA circuit for filtering two closely adjacent signals
CAn FM generator circuit
DA circuit for detecting FM signals

36. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

SelectAnswer
AIt removes high-frequency signal components that would otherwise be reproduced as lower frequency components
BIt notches out the sampling frequency to avoid sampling errors
CIt removes low-frequency signal components to eliminate the need for DC restoration
DIt peaks the response of the decimator, improving bandwidth

37. - E7G02

What is ringing in a filter?

SelectAnswer
AAn echo caused by a long time delay
BPartial cancellation of the signal over a range of frequencies
CA reduction in high frequency response
DUndesired oscillations added to the desired signal

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 servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
CAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
DAn electronic circuit also known as a monostable multivibrator

39. - E8A09

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

SelectAnswer
A256 divided by the gain of the input amplifier
B8
C8 multiplied by the gain of the input amplifier
D256

40. - E8B10

What is frequency division multiplexing?

SelectAnswer
AThe transmitted signal is divided into packets of information
BTwo or more information streams are merged into a baseband, which then modulates the transmitter
CTwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
DThe transmitted signal jumps from band to band at a predetermined rate

41. - E8C10

How may data rate be increased without increasing bandwidth?

SelectAnswer
AUsing a more efficient digital code
BUsing forward error correction
CIt is impossible
DIncreasing analog-to-digital conversion resolution

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
BBaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
CBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
DBaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code

43. - E9A05

What is included in the total resistance of an antenna system?

SelectAnswer
ARadiation resistance plus transmission resistance
BTransmission-line resistance plus radiation resistance
CRadiation resistance plus loss resistance
DRadiation resistance plus space impedance

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
ACalculus differentiation with respect to physical properties
BMutual impedance analysis
CGraphical analysis
DMethod of Moments

45. - E9C08

What is a folded dipole antenna?

SelectAnswer
AA type of ground-plane antenna
BA half-wave dipole with an additional parallel wire connecting its two ends
CA dipole one-quarter wavelength long
DA dipole configured to provide forward gain

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

47. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

SelectAnswer
AThe delta match
BThe omega match
CThe stub match
DThe gamma match

48. - E9F13

What impedance does a 1/4-wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AVery high impedance
BThe same as the generator output impedance
CThe same as the characteristic impedance of the transmission line
DVery low impedance

49. - E9G01

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

SelectAnswer
AAntenna radiation pattern
BImpedance along transmission lines
CRadiation resistance
DRadio propagation

50. - E9H04

What is an advantage of placing a grounded electrostatic shield around a small loop direction-finding antenna?

SelectAnswer
AIt eliminates unbalanced capacitive coupling to the surroundings, improving the nulls
BIt eliminates tracking errors caused by strong out-of-band signals
CIt adds capacitive loading, increasing the bandwidth of the antenna
DIt increases signal strength by providing a better match to the feed line

Figure E7-1