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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

SelectAnswer
AAt the highest frequency of the channel
BAt the lowest frequency of the channel
CAt the center frequency of the channel
DOn any frequency where the signal's sidebands are within the channel

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

SelectAnswer
ASpecific segments in the amateur service MF, HF, VHF and UHF bands
BMilitary Auxiliary Radio System (MARS) channels
CAll amateur service frequencies authorized to the control operator
DSpecific local government channels

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

SelectAnswer
AAll of these choices are correct
BCEPT agreement
CITU reciprocal license
DIARP agreement

4. - E1D03

What is a telecommand station in the amateur satellite service?

SelectAnswer
AAn amateur station that transmits telemetry consisting of measurements of upper atmosphere
BAn amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
CAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
DAn amateur station located more than 50 km above the Earth's surface

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

SelectAnswer
AThe prospective VE obtains accreditation from the FCC
BThe amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
CEach General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
DThe procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

SelectAnswer
A440 MHz - 450 MHz
B222 MHz - 223 MHz
C53 MHz - 54 MHz
D420 MHz - 430 MHz

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

SelectAnswer
ABecause of the satellite's low orbital altitude
BBecause of the Doppler Effect
CBecause of ionospheric absorption
DBecause the satellite is spinning

8. - E2B04

What is blanking in a video signal?

SelectAnswer
ATransmitting a black and white test pattern
BTurning off the scanning beam while it is traveling from right to left or from bottom to top
CSynchronization of the horizontal and vertical sync pulses
DTurning off the scanning beam at the conclusion of a transmission

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

SelectAnswer
ASend your full call sign and grid square
BSend the call sign of the DX station three times, the words "this is", then your call sign three times
CSend only the last two letters of your call sign until you make contact
DSend your full call sign once or twice

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

SelectAnswer
ADigipeating
BStore-and-forward
CNode hopping
DMulti-satellite relaying

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

SelectAnswer
ARTTY
BPSK31
CMFSK
DWinlink

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

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

13. - E3B10

What is the cause of gray-line propagation?

SelectAnswer
AAt midday, the Sun super heats the ionosphere causing increased refraction of radio waves
BAt mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
CIn darkness, solar absorption drops greatly while atmospheric ionization remains steady
DAt twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high

14. - E3C01

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

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

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

SelectAnswer
AAll of these choices are correct
BUse high quality double shielded coaxial cables to reduce signal losses
CMatch the antenna to the load
DAttenuate the transmitter output going to the spectrum analyzer

16. - E4B16

Which S parameter represents return loss or SWR?

SelectAnswer
AS22
BS11
CS12
DS21

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

SelectAnswer
A-155 dBm
B-148 dBm
C-164 dBm
D-174 dBm

18. - E4D01

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

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

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

SelectAnswer
ANearby corroded metal joints are mixing and re-radiating the broadcast signals
BThe broadcast station is transmitting an over-modulated signal
CYour station receiver IF amplifier stage is defective
DYou are receiving sky wave signals from a distant station

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

SelectAnswer
A15.7 kHz
B436.6 kHz
C218.3 kHz
D31.4 kHz

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

SelectAnswer
AIt is shifted by 90 degrees
BThe sign is reversed
CIt is unchanged
DThe susceptance phase angle is the inverse of the reactance phase angle

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

SelectAnswer
A+jX
B-jX
CX
DOmega

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

SelectAnswer
A355 W
B704 W
C252 W
D1.42 mW

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

SelectAnswer
ABipolar-type
BSuperconductor-type
CN-type
DP-type

25. - E6B01

What is the most useful characteristic of a Zener diode?

SelectAnswer
AA constant voltage drop under conditions of varying current
BA constant current drop under conditions of varying voltage
CAn internal capacitance that varies with the applied voltage
DA negative resistance region

26. - E6C12

What is BiCMOS logic?

SelectAnswer
AAn integrated circuit logic family using both bipolar and CMOS transistors
BA FET logic family based on bimetallic semiconductors
CA logic family based on bismuth CMOS devices
DA logic device with two CMOS circuits per package

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

SelectAnswer
AButterworth filters
BFerrite beads
CSteel-core toroids
DElectrolytic capacitors

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

SelectAnswer
ADirect soldering
BVirtual lead mounting
CSurface mount
DStripped lead

29. - E6F01

What is photoconductivity?

SelectAnswer
AThe increased conductivity of an illuminated semiconductor
BThe conversion of electromotive energy to photon energy
CThe decreased conductivity of an illuminated semiconductor
DThe conversion of photon energy to electromotive energy

30. - E7A02

What is the function of a decade counter digital IC?

SelectAnswer
AIt decodes a decimal number for display on a seven segment LED display
BIt adds two decimal numbers together
CIt produces ten output pulses for every input pulse
DIt produces one output pulse for every ten input pulses

31. - E7B12

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

SelectAnswer
ACommon collector
BCommon emitter
CCommon base
DEmitter follower

32. - 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

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

SelectAnswer
AVoltage difference from input to output multiplied by output current
BInput voltage divided by output current
COutput voltage multiplied by output current
DInput voltage multiplied by input current

34. - E7E07

What is meant by the term baseband in radio communications?

SelectAnswer
AThe lowest frequency band that the transmitter or receiver covers
BThe unmodulated bandwidth of the transmitted signal
CThe frequency components present in the modulating signal
DThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency

35. - E7F07

What function can a Fast Fourier Transform perform?

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

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

SelectAnswer
ANon-inductive resistors
BNP0 capacitors
CToroidal inductors
DWirewound resistors

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

SelectAnswer
ABy using an absorption wave meter
BBy measuring the voltage with a D'Arsonval meter
CBy using a grid dip meter
DBy measuring the heating effect in a known resistor

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

SelectAnswer
A2.14
B47
C0.47
D0.214

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

SelectAnswer
AExtended Binary Coded Decimal Interchange Code
BExcess 3 code
CBinary Coded Decimal Code
DGray code

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

SelectAnswer
AMore difficult to copy
BThe generation of RF harmonics
CThe generation of key clicks
DLimits data speed

42. - E9A08

What is meant by antenna bandwidth?

SelectAnswer
AAntenna length divided by the number of elements
BThe angle formed between two imaginary lines drawn through the element ends
CThe frequency range over which an antenna satisfies a performance requirement
DThe angle between the half-power radiation points

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

SelectAnswer
AFeed point impedance may become negative
BThe gain may change depending on frequency
CElement spacing limits could be exceeded
DThe E-field and H-field patterns may reverse

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

SelectAnswer
ABoth the high-angle and low-angle radiation decrease
BThe low-angle radiation increases
CThe high-angle radiation increases
DThe low-angle radiation decreases

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

SelectAnswer
ATo minimize the Q
BTo swamp out harmonics
CTo minimize losses
DTo maximize losses

46. - E9E13

What is a use for a Wilkinson divider?

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

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
B20 meters
C0.2 meters
D2.3 meters

48. - E9G03

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

SelectAnswer
ATrigonometric functions
BBeam headings and radiation patterns
CSatellite azimuth and elevation bearings
DImpedance and SWR values in transmission lines

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

SelectAnswer
AA very sharp peak
BA very sharp single null
CBroad band response
DHigh-radiation angle

50. - E0A06

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

SelectAnswer
AThe body reacts to electromagnetic radiation from both the E and H fields
BE field and H field radiation intensity peaks can occur at different locations
CAll of these choices are correct
DGround reflections and scattering make the field impedance vary with location

Figure E7-1