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US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

SelectAnswer
A30 meter band
B17 meter band
C60 meter band
D12 meter band

2. - 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
BNo special rules apply if your antenna structure will be less than 300 feet in height
CYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
DYou must file an Environmental Impact Statement with the EPA before construction begins

3. - E1C07

What is meant by local control?

SelectAnswer
AControlling a station through a local auxiliary link
BDirect manipulation of the transmitter by a control operator
CControlling a repeater using a portable handheld transceiver
DAutomatically manipulating local station controls

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

SelectAnswer
AAny amateur station designated by NASA
BAny amateur station so designated by the ITU
CAll of these choices are correct
DAny amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

SelectAnswer
AIn a question pool maintained by all the VECs
BIn the appropriate FCC Report and Order
CIn FCC Part 97
DIn a question pool maintained by the FCC

6. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

SelectAnswer
AA line roughly parallel to and east of the U.S. Pacific coastline
BA line roughly parallel to and west of the U.S. Atlantic coastline
CA line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
DA line roughly parallel to and south of the U.S.-Canadian border

7. - E2A04

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

SelectAnswer
AThe satellite's orientation with respect to the Earth
BThe satellite's uplink and downlink frequency bands
CThe type of signals that can be relayed through the satellite
DWhether the satellite is in a polar or equatorial orbit

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

SelectAnswer
AAll of these choices are correct
BFrequency-modulated sub-carrier
CFrequency modulation of the video carrier
DA separate VHF or UHF audio link

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the 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
DThe ARRL section of the remote station

10. - E2D06

Which of the following describes a method of establishing EME contacts?

SelectAnswer
AStoring and forwarding digital messages
BHigh speed CW identification to avoid fading
CTime synchronous transmissions alternately from each station
DJudging optimum transmission times by monitoring beacons reflected from the Moon

11. - E2E06

What is the most common data rate used for HF packet?

SelectAnswer
A1200 baud
B48 baud
C110 baud
D300 baud

12. - E3A12

What is the cause of auroral activity?

SelectAnswer
AThe interaction in the F2 layer between the solar wind and the Van Allen belt
BA low sunspot level combined with tropospheric ducting
CThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
DMeteor showers concentrated in the extreme northern and southern latitudes

13. - E3B13

Why is chordal hop propagation desirable?

SelectAnswer
AThe MUF for chordal hop propagation is much lower than for normal skip propagation
BAtmospheric noise is lower in the direction of chordal hop propagation
CThe signal experiences less loss along the path compared to normal skip propagation
DSignals travel faster along ionospheric chords

14. - E3C13

What type of polarization is best for ground-wave propagation?

SelectAnswer
AElliptical
BVertical
CHorizontal
DCircular

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

SelectAnswer
AFalse signals are displayed
BCalibration of the vertical scale is no longer valid
CFalse triggering occurs
DAll signals will have a DC offset

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A165.2 Hz
B146.52 Hz
C14.652 kHz
D1.4652 MHz

17. - E4C13

How does a narrow-band roofing filter affect receiver performance?

SelectAnswer
AAll of these choices are correct
BIt improves sensitivity by reducing front end noise
CIt improves dynamic range by attenuating strong signals near the receive frequency
DIt improves intelligibility by using low Q circuitry to reduce ringing

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

SelectAnswer
AThe difference in dB between the noise floor and the third order intercept point
BThe minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
CThe difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
DThe minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

SelectAnswer
AAny nearby signal passing through the DSP system will overwhelm the desired signal
BReceived CW signals will appear to be modulated at the DSP clock frequency
CA DSP filter can remove the desired signal at the same time as it removes interfering signals
DRinging in the DSP filter will completely remove the spaces between the CW characters

20. - E5A11

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

SelectAnswer
A47.3 kHz
B157.8 Hz
C315.6 Hz
D23.67 kHz

21. - 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 leading the current
B14.0 degrees with the voltage leading the current
C14.0 degrees with the voltage lagging the current
D68.2 degrees with the voltage lagging the current

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

SelectAnswer
AA negative phase angle
BA negative real part
CA positive phase angle
DA positive real part

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

SelectAnswer
ABy multiplying the reactive power times the power factor
BBy multiplying the apparent power times the power factor
CBy dividing the reactive power by the power factor
DBy dividing the apparent power by the power factor

24. - E6A17

What are the names of the three terminals of a field-effect transistor?

SelectAnswer
AEmitter, base, collector
BGate, drain, source
CGate 1, gate 2, drain
DEmitter, base 1, base 2

25. - E6B13

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

SelectAnswer
AInductive bias
BZero bias
CReverse bias
DForward bias

26. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AAn algorithm for simulating logic functions during circuit design
BProgrammable equipment used for testing digital logic integrated circuits
CA programmable collection of logic gates and circuits in a single integrated circuit
DA device to control industrial equipment

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

SelectAnswer
AMagnetic flux would increase with frequency
BHarmonics and distortion could result
CTemporary changes of the core permeability could result
DRF susceptance would increase

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

SelectAnswer
AMicrostrip construction
BPoint-to-point construction
CGround-plane construction
DWave-soldering construction

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

SelectAnswer
APhotons
BProtons
CElectrons
DHoles

30. - E7A04

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

SelectAnswer
A4
B1
C2
D8

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

SelectAnswer
AThe entire cycle
BExactly 180 degrees
CMore than 180 degrees but less than 360 degrees
DLess than 180 degrees

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-3?

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

34. - E7E11

Which type of detector is used for demodulating SSB signals?

SelectAnswer
ADiscriminator
BProduct detector
CPhase comparator
DPhase detector

35. - E7F09

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

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

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

SelectAnswer
A76
B38
C1
D0.03

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

SelectAnswer
AThe phase relationship between a reference oscillator and the output waveform
BThe amplitude values that represent a sine-wave output
CThe synthesizer frequency limits and frequency values stored in the radio memories
DThe phase relationship between a voltage-controlled oscillator and the output waveform

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

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

39. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

SelectAnswer
A3000
B1000
C3
D0.3

40. - E8C01

How is Forward Error Correction implemented?

SelectAnswer
ABy transmitting extra data that may be used to detect and correct transmission errors
BBy the receiving station repeating each block of three data characters
CBy varying the frequency shift of the transmitted signal according to a predefined algorithm
DBy transmitting a special algorithm to the receiving station along with the data characters

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

SelectAnswer
ABit errors in the modem
BExcessive numbers of retries
CGround loops
DExcessive transmit audio levels

42. - E9A09

How is antenna efficiency calculated?

SelectAnswer
A(total resistance / radiation resistance) x 100 per cent
B(radiation resistance / transmission resistance) x 100 per cent
C(effective radiated power / transmitter output) x 100 percent
D(radiation resistance / total resistance) x 100 per cent

43. - E9B09

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

SelectAnswer
AMutual impedance analysis
BGraphical analysis
CMethod of Moments
DCalculus differentiation with respect to physical properties

44. - E9C08

What is a folded dipole antenna?

SelectAnswer
AA dipole consisting of one wavelength of wire forming a very thin loop
BA dipole configured to provide forward gain
CA type of ground-plane antenna
DA dipole one-quarter wavelength long

45. - E9D13

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

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

46. - E9E13

What is a use for a Wilkinson divider?

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

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

SelectAnswer
AVelocity factor
BStanding wave ratio
CCharacteristic impedance
DSurge impedance

48. - E9G03

Which of the following is often determined using a Smith chart?

SelectAnswer
AImpedance and SWR values in transmission lines
BTrigonometric functions
CBeam headings and radiation patterns
DSatellite azimuth and elevation bearings

49. - E9H08

What is the function of a sense antenna?

SelectAnswer
AIt allows DF antennas to receive signals at different vertical angles
BIt provides diversity reception that cancels multipath signals
CIt modifies the pattern of a DF antenna array to provide a null in one direction
DIt increases the sensitivity of a DF antenna array

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

SelectAnswer
AOnly with a carbon monoxide detector
BBy the odor
CAny ordinary smoke detector can be used
DBy the yellowish appearance of the gas

Figure E7-3

Figure E7-4