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

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1. - E1A09

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

SelectAnswer
ADiscontinue forwarding the communication as soon as you become aware of it
BNotify the nearest FCC Field Engineer's office
CDiscontinue forwarding all messages
DNotify the originating station that the communication does not comply with FCC rules

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

SelectAnswer
AA letter of intent must be filed with the National Audubon Society
BA proposal must be submitted to the National Park Service
CA form FSD-15 must be submitted to the Department of the Interior
DAn Environmental Assessment must be submitted to the FCC

3. - E1C02

What is meant by automatic control of a station?

SelectAnswer
AThe use of devices and procedures for control so that the control operator does not have to be present at a control point
BA station operating with its output power controlled automatically
CThe use of a control link between a control point and a locally controlled station
DRemotely controlling a station's antenna pattern through a directional control link

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

SelectAnswer
A70 cm only
B33 cm and 13 cm
C70 cm and 13 cm
D70 cm and 33 cm

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 FCC Part 97
CIn the appropriate FCC Report and Order
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 north of the U.S.-Mexican border and Gulf coastline
CA line roughly parallel to and west of the U.S. Atlantic coastline
DA line roughly parallel to and south of the U.S.-Canadian border

7. - E2A01

What is the direction of an ascending pass for an amateur satellite?

SelectAnswer
AFrom east to west
BFrom south to north
CFrom north to south
DFrom west to east

8. - E2B15

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

SelectAnswer
AElapsed time
BSpecific tone frequencies
CSpecific tone amplitudes
DA two-tone signal

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

SelectAnswer
AWait 90 minutes or so for the signal degradation to pass
BSwitch to a higher frequency HF band
CSwitch to a lower frequency HF band
DWait 24 hours before attempting another communication on the band

10. - E2D12

How does JT65 improve EME communications?

SelectAnswer
AIt controls the receiver to track Doppler shift
BAll of these choices are correct
CIt supplies signals to guide the antenna to track the Moon
DIt can decode signals many dB below the noise floor using FEC

11. - E2E13

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

SelectAnswer
AAnother station you are unable to hear is using the frequency
BAll of these choices are correct
CThe protocol version you are using is not the supported by the digital station
DYour transmit frequency is incorrect

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

SelectAnswer
ARain droplets must be electrically charged
BThe rain must be within radio range of both stations
CRain droplets must be within the E layer
DAll of these choices are correct

13. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between any two points located on the magnetic equator
BPropagation between two continents by way of ducts along the magnetic equator
CPropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
DPropagation between two stations at the same latitude

14. - E3C01

What does the term ray tracing describe in regard to radio communications?

SelectAnswer
AEvaluating high voltage sources for X-Rays
BModeling a radio wave's path through the ionosphere
CThe process in which an electronic display presents a pattern
DDetermining the radiation pattern from an array of antennas

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

SelectAnswer
AIt can directly measure the modulation index of an FM transmitter
BIt can run on battery power for remote measurements
CIt does not require an expensive high-precision time base
DIt provides improved resolution of low-frequency signals within a comparable time period

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
A14.652 kHz
B165.2 Hz
C146.52 Hz
D1.4652 MHz

17. - E4C07

What does the MDS of a receiver represent?

SelectAnswer
AThe meter display sensitivity
BThe minimum discernible signal
CThe multiplex distortion stability
DThe maximum detectable spectrum

18. - E4D03

How can intermodulation interference between two repeaters occur?

SelectAnswer
AWhen the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
BWhen the signals from the transmitters are reflected in phase from airplanes passing overhead
CWhen the signals from the transmitters are reflected out of phase from airplanes passing overhead
DWhen the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

SelectAnswer
AHarmonics of the AC power line frequency
BA common-mode signal at the frequency of the radio transmitter
CAn electrical-sparking signal
DA differential-mode signal at the AC power line frequency

20. - E5A15

Which of the following can increase Q for inductors and capacitors?

SelectAnswer
ALower self-resonant frequency
BLower losses
CHigher self-resonant frequency
DLower reactance

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

SelectAnswer
A76 degrees with the voltage leading the current
B76 degrees with the voltage lagging the current
C14 degrees with the voltage leading the current
D14 degrees with the voltage lagging the current

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

SelectAnswer
APoint 7
BPoint 8
CPoint 1
DPoint 3

23. - E5D08

What type of energy is stored in an electromagnetic or electrostatic field?

SelectAnswer
APotential energy
BThermodynamic energy
CElectromechanical energy
DKinetic energy

24. - E6A13

What do the initials CMOS stand for?

SelectAnswer
AComplementary Mica-Oxide Silicon
BComplementary Metal-Oxide Semiconductor
CCommon Mode Organic Silicon
DCommon Mode Oscillating System

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

SelectAnswer
AVaractor diode
BTunnel diode
CZener diode
DSilicon-controlled rectifier

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

SelectAnswer
AIts simplicity results in much less expensive devices than standard CMOS
BIt has the high input impedance of CMOS and the low output impedance of bipolar transistors
CIt is totally immune to electrostatic damage
DAll of these choices are correct

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

SelectAnswer
ACeramic
BFerrite
CPowdered-iron
DBrass

28. - E6E07

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

SelectAnswer
APoint-to-point construction
BWave-soldering construction
CGround-plane construction
DMicrostrip construction

29. - E6F13

What is a liquid crystal display (LCD)?

SelectAnswer
AA display that uses a glowing liquid to remain brightly lit in dim light
BA modern replacement for a quartz crystal oscillator which displays its fundamental frequency
CA display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
DA frequency-determining unit for a transmitter or receiver

30. - E7A06

What is a characteristic of a monostable multivibrator?

SelectAnswer
AIt produces a continuous square wave oscillating between 1 and 0
BIt stores one bit of data in either a 0 or 1 state
CIt switches momentarily to the opposite binary state and then returns to its original state after a set time
DIt maintains a constant output voltage, regardless of variations in the input voltage

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

SelectAnswer
ALow efficiency
BAll of these choices are correct
CCreation of parasitic oscillations
DTransmission of spurious signals

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

SelectAnswer
APi-networks are designed for balanced input and output
BL-networks cannot perform impedance transformation
CThe Q of Pi-networks can be varied depending on the component values chosen
DPi-networks have fewer components

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
APhase comparator
BPhase detector
CProduct detector
DDiscriminator

35. - E7F07

What function can a Fast Fourier Transform perform?

SelectAnswer
AConverting analog signals to digital form
BConverting 8-bit data to 16 bit data
CConverting digital signals to analog form
DConverting digital signals from the time domain to the frequency domain

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
B1
C0.03
D38

37. - E7H13

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

SelectAnswer
AUse a GPS signal reference
BAll of these choices are correct
CUse a rubidium stabilized reference oscillator
DUse a temperature-controlled high Q dielectric resonator

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AAll of these choices are correct
BVery low power consumption decreases frequency drift
CImmunity to out of sequence coding reduces spurious responses
DVery high speed allows digitizing high frequencies

39. - 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
A6000
B3
C1/3
D2000

40. - E8C07

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

SelectAnswer
A5.76 kHz
B9.6 kHz
C4.8 kHz
D15.36 kHz

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
APhase compandored spread spectrum
BBinary phase-shift keying
CDirect sequence
DFrequency hopping

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

SelectAnswer
A78.7 watts
B1977 watts
C286 watts
D420 watts

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

SelectAnswer
AMeasure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
BMeasure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
CDraw two imaginary lines through the ends of the elements and measure the angle between the lines
DNote the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

SelectAnswer
AThe horizontal beam width decreases with height
BThe main lobe takeoff angle increases with increasing height
CThe main lobe takeoff angle decreases with increasing height
DThe horizontal beam width increases with height

45. - E9D13

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

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

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

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

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

SelectAnswer
A3.5 meters
B0.2 meters
C20 meters
D2.3 meters

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

SelectAnswer
APrime axis
BPolar axis
CReactance axis
DImpedance axis

49. - E9H02

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

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

50. - E0A01

What is the primary function of an external earth connection or ground rod?

SelectAnswer
ALightning protection
BReduce received noise
CReduce RF current flow between pieces of equipment
DReduce RFI to telephones and home entertainment systems

Figure E5-2

Figure E7-3

Figure E7-4

Figure E9-3