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

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1. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

SelectAnswer
AGround reflections and scattering make the field strength vary with location
BThe body reacts to electromagnetic radiation from both the E and H fields
CE field and H field radiation intensity peaks can occur at different locations
DAll these choices are correct

2. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

SelectAnswer
AThe amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
BThe amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use
CIts operation must be approved by the master of the ship or the pilot in command of the aircraft
DThe amateur station must have a power supply that is completely independent of the main ship or aircraft power supply

3. - E1B09

Which amateur stations may be operated under RACES rules?

SelectAnswer
AAny FCC-licensed amateur station except a Technician Class
BAny FCC-licensed amateur station certified by the responsible civil defense organization for the area served
CAny FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
DOnly those club stations licensed to Amateur Extra Class operators

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

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

SelectAnswer
AA message forwarding station or automatically controlled digital station
BAll these choices are correct
CA local repeater or linked repeater station
DA space station, beacon station, or telecommand station

6. - E1E06

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

SelectAnswer
AThe VE session manager
BThe FCC
CThe VEC coordinating the session
DEach administering VE

7. - E1F09

Which of the following conditions apply when transmitting spread spectrum emissions?

SelectAnswer
AThe transmission must not be used to obscure the meaning of any communication
BAll these choices are correct
CA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
DThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions

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
AA special notch filter to remove synchronization pulses
BA special front end limiter
CNo other hardware is needed
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/R# where # is the district of the remote station
CNo additional indicator is required
D/ followed by the ARRL Section of the remote station

11. - E2D10

How can an APRS station be used to help support a public service communications activity?

SelectAnswer
AAll these choices are correct
BAn APRS station with a Global Positioning System unit can automatically transmit information to show a mobile station's position during the event
CAn APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
DAPRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points

12. - E2E03

How is the timing of FT4 contacts organized?

SelectAnswer
AStations take turns on alternate days
BBy exchanging ACK/NAK packets
CAlternating transmissions at 7.5 second intervals
DIt depends on the lunar phase

13. - E3A12

What is the cause of auroral activity?

SelectAnswer
AThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
BThe interaction in the F2 layer between the solar wind and the Van Allen belt
CMeteor showers concentrated in the extreme northern and southern latitudes
DAn extreme low-pressure area in the polar regions

14. - E3B04

What is meant by the terms "extraordinary" and "ordinary" waves?

SelectAnswer
AExtraordinary waves describe rare long-skip propagation compared to ordinary waves, which travel shorter distances
BIndependent waves created in the ionosphere that are elliptically polarized
CRefracted rays and reflected waves
DLong-path and short-path waves

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
CWestward
DNorthward

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
BConnect the antenna feed line directly to the analyzer's connector
CLoosely couple the analyzer near the antenna base
DConnect the analyzer via a high-impedance transformer to the antenna

17. - E4B11

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

SelectAnswer
AOutput impedance
BReflection coefficient
CInput impedance
DAll these choices are correct

18. - E4C10

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

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

19. - E4D12

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

SelectAnswer
ASquelch gain rollback
BQuieting
CCross-modulation interference
DDesensitization

20. - E4E10

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

SelectAnswer
AA malfunctioning illuminated advertising display
BAll these choices are correct
CA defective doorbell or doorbell transformer inside a nearby residence
DArcing contacts in a thermostatically controlled device

21. - E5A13

What is an effect of increasing Q in a series resonant circuit?

SelectAnswer
APhase shift can become uncontrolled
BFewer components are needed for the same performance
CInternal voltages increase
DParasitic effects are minimized

22. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

SelectAnswer
A68.2 degrees with the voltage lagging the current
B14.0 degrees with the voltage leading the current
C68.2 degrees with the voltage leading the current
D14.0 degrees with the voltage lagging the current

23. - E5C12

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

SelectAnswer
APoint 7
BPoint 8
CPoint 3
DPoint 1

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
A50 watts
B80 watts
C400 watts
D2000 watts

25. - E6A10

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

SelectAnswer
A2
B5
C4
D6

26. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

SelectAnswer
ACharge carrier depletion
BExcessive inverse voltage
CInsufficient forward voltage
DExcessive junction temperature

27. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
ALower power consumption
BLower distortion
CImmune to damage from static discharge
DDifferential output capability

28. - E6D06

What core material property determines the inductance of an inductor?

SelectAnswer
APermeability
BThermal impedance
CReactivity
DResistance

29. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

SelectAnswer
ASurface mount
BRadial lead
CAxial lead
DTO-220

30. - E6F09

What is the efficiency of a photovoltaic cell?

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

31. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

SelectAnswer
A2
B4
C1
D8

32. - E7B12

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

SelectAnswer
ACommon collector
BEmitter follower
CCommon base
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
AGreater transformation range
BGreater harmonic suppression
CDoes not require a capacitor
DHigher efficiency

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

SelectAnswer
AMinimum input-to-output voltage required to maintain regulation
BMinimum input voltage for rated power dissipation
CMaximum that the output voltage may decrease at rated load
DMaximum output voltage drops when the input voltage is varied over its specified range

35. - E7E05

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

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

36. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

SelectAnswer
AHigher data rate
BDouble-precision math routines
CMore taps
DComplex phasor representations

37. - E7G04

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

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

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

SelectAnswer
AColpitts, Hartley and Pierce
BTaft, Pierce and negative feedback
CPierce, Fenner and Beane
DTaft, Hartley and Pierce

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

SelectAnswer
AHarmonic regeneration
BSuccessive approximation
CLevel shifting
DPhase reversal

40. - E8B01

What is the modulation index of an FM signal?

SelectAnswer
AThe bandwidth of the transmitted signal divided by the modulating signal frequency
BThe ratio of frequency deviation to modulating signal frequency
CThe type of modulation used by the transmitter
DThe ratio of modulating signal amplitude to frequency deviation

41. - E8C09

Which digital code allows only one bit to change between sequential code values?

SelectAnswer
AExtended Binary Coded Decimal Interchange Code
BExcess 3 code
CGray code
DBinary Coded Decimal Code

42. - E8D11

What is one advantage of using ASCII code for data communications?

SelectAnswer
AIt contains fewer information bits per character than any other code
BIt includes built-in error correction features
CIt uses one character as a shift code to send numeric and special characters
DIt is possible to transmit both upper and lower case text

43. - E9A01

What is an isotropic antenna?

SelectAnswer
AA spacecraft antenna used to direct signals toward Earth
BA theoretical, omnidirectional antenna used as a reference for antenna gain
CA horizontally polarized antenna used to compare Yagi antennas
DA grounded antenna used to measure Earth conductivity

44. - E9B05

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

SelectAnswer
ARadiation resistance
BElevation
CPolarization
DAzimuth

45. - E9C06

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

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

46. - E9D06

What happens to the SWR bandwidth when one or more loading coils are used to resonate an electrically short antenna?

SelectAnswer
AIt is unchanged if the loading coil is located at a voltage maximum point
BIt is unchanged if the loading coil is located at the feed point
CIt is decreased
DIt is increased

47. - E9E10

Which of these choices is an effective way to match an antenna with a 100-ohm feed point impedance to a 50-ohm coaxial cable feed line?

SelectAnswer
AConnect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna
BConnect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna
CInsert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable
DInsert a 1/4-wavelength piece of 75-ohm coaxial cable transmission line in series between the antenna terminals and the 50-ohm feed cable

48. - E9F11

What impedance does a 1/8-wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AAn inductive reactance
BThe same as the characteristic impedance of the line
CA capacitive reactance
DInfinite

49. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

SelectAnswer
AThe voltage axis
BThe reactance axis
CThe current axis
DThe resistance axis

50. - E9H07

Why is RF attenuation used when direction-finding?

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

Figure E5-1

Figure E6-1

Figure E7-1

Figure E9-2

Figure E9-3