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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

SelectAnswer
AThe exact lower band edge
B3 kHz above the lower band edge
C1 kHz above the lower band edge
D300 Hz above the lower band edge

2. - E1B05

What is the National Radio Quiet Zone?

SelectAnswer
AAn area in Florida surrounding Cape Canaveral
BAn area surrounding the National Radio Astronomy Observatory
CAn area in Puerto Rico surrounding the Arecibo Radio Telescope
DAn area in New Mexico surrounding the White Sands Test Area

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

SelectAnswer
AUnder local control there is no control operator
BUnder local control a control operator is not required to be present at a control point
CUnder automatic control there is no control operator
DUnder automatic control the control operator is not required to be present at the control point

4. - E1D02

What is the amateur satellite service?

SelectAnswer
AA radio communications service using stations on Earth satellites for public service broadcast
BA radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
CA radio communications service using amateur radio stations on satellites
DA spacecraft launching service for amateur-built satellites

5. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
AEmployees of the VE
BFriends of the VE
CRelatives of the VE as listed in the FCC rules
DAll of these choices are correct

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
A53 MHz - 54 MHz
B222 MHz - 223 MHz
C440 MHz - 450 MHz
D420 MHz - 430 MHz

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

SelectAnswer
ARadar
BAPRS
CBandwidth compressed LORAN
DDoppler shift of beacon signals

8. - E2B06

What is vestigial sideband modulation?

SelectAnswer
ASpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
BAmplitude modulation in which one complete sideband and a portion of the other are transmitted
CNarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
DA type of modulation in which one sideband is inverted

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

SelectAnswer
AThe acceptable practice of manually posting the call signs of stations on a spotting network
BA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
CAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
DThe generally prohibited practice of posting one's own call sign and frequency on a spotting network

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
ADisconnect
BAcknowledgement
CConnect
DUnnumbered Information

11. - E2E11

What is the difference between direct FSK and audio FSK?

SelectAnswer
AAudio FSK can be performed anywhere in the transmit chain
BDirect FSK uses a DC-coupled data connection
CAudio FSK has a superior frequency response
DDirect FSK applies the data signal to the transmitter VFO

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
BThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
CMeteor showers concentrated in the extreme northern and southern latitudes
DA low sunspot level combined with tropospheric ducting

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A5000 miles
B2500 miles
C1000 miles
D7500 miles

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

SelectAnswer
ATransequatorial propagation
BNVIS
CPolar paths
DSporadic-E

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

SelectAnswer
AInput impedance
BInput capacitance
CSample resolution
DSampling rate

16. - E4B12

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 a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
DWhen used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

SelectAnswer
AIt can cause strong signals on nearby frequencies to interfere with reception of weak signals
BIt decreases receiver third-order intermodulation distortion dynamic range
CIt limits the receiver's ability to receive strong signals
DIt reduces receiver sensitivity

18. - E4D12

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

SelectAnswer
ACross-modulation interference
BDesensitization
CQuieting
DSquelch gain rollback

19. - E4E13

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
BArcing contacts in a thermostatically controlled device
CAll of these choices are correct
DA defective doorbell or doorbell transformer inside a nearby residence

20. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

SelectAnswer
AMinimum
BMaximum
CL/R
DR/L

21. - E5B06

What is susceptance?

SelectAnswer
AThe ratio of magnetic field to electric field
BA measure of the efficiency of a transformer
CThe magnetic impedance of a circuit
DThe inverse of reactance

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

SelectAnswer
AThe difference between the resistive and reactive components
BReactive component
CThe sum of the reactive and resistive components
DResistive component

23. - E5D08

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

SelectAnswer
AThermodynamic energy
BElectromechanical energy
CPotential energy
DKinetic energy

24. - E6A13

What do the initials CMOS stand for?

SelectAnswer
ACommon Mode Oscillating System
BCommon Mode Organic Silicon
CComplementary Metal-Oxide Semiconductor
DComplementary Mica-Oxide Silicon

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

SelectAnswer
AZener
BPoint contact
CTunnel
DJunction

26. - E6C08

In Figure E6-5, what is the schematic symbol for a NAND gate?

SelectAnswer
A1
B4
C3
D2

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

SelectAnswer
AFerrite toroids generally have lower initial permeability
BFerrite toroids are easier to use with surface mount technology
CFerrite toroids generally have better temperature stability
DFerrite toroids generally require fewer turns to produce a given inductance value

28. - E6E09

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

SelectAnswer
ASurface mount
BAxial lead
CRadial lead
DTO-220

29. - E6F07

What is a solid state relay?

SelectAnswer
AA mechanical relay that latches in the on or off state each time it is pulsed
BA relay using transistors to drive the relay coil
CA passive delay line
DA device that uses semiconductors to implement the functions of an electromechanical relay

30. - E7A10

What is a truth table?

SelectAnswer
AA diagram showing logic states when the digital device output is true
BA table of logic symbols that indicate the logic states of an op-amp
CA list of inputs and corresponding outputs for a digital device
DA table of logic symbols that indicate the high logic states of an op-amp

31. - E7B12

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

SelectAnswer
AEmitter follower
BCommon emitter
CCommon base
DCommon collector

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

SelectAnswer
AThe amplitude of the signals passing through the filter
BThe DC voltage applied to the quartz crystal
CThe gain of the RF stage preceding the filter
DThe relative frequencies of the individual crystals

33. - E7D08

What type of circuit is shown in Figure E7-3?

SelectAnswer
AEmitter follower
BSwitching voltage regulator
CLinear voltage regulator
DGrounded emitter amplifier

34. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy driving a product detector with a DSB signal
BBy using a reactance modulator followed by a mixer
CBy using a balanced modulator followed by a filter
DBy using a loop modulator followed by a mixer

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
AIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
BSoftware is converted from source code to object code during operation of the receiver
CA switching mixer is used to generate I and Q signals directly from the RF input
DIncoming RF is converted to a control voltage for a voltage controlled oscillator

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt decreases logarithmically with increasing frequency
BIt increases linearly with increasing frequency
CIt decreases linearly with increasing frequency
DIt does not vary with frequency

37. - E7H13

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

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

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

SelectAnswer
AA sawtooth wave
BA square wave
CA cosine wave
DA sine wave

39. - E8B10

What describes frequency division multiplexing?

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

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

SelectAnswer
AApproximately 52 Hz
BApproximately 26 Hz
CApproximately 13 Hz
DApproximately 104 Hz

41. - E8D02

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

SelectAnswer
AFrequency hopping
BBinary phase-shift keying
CDirect sequence
DPhase compandored spread spectrum

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
A420 watts
B78.7 watts
C286 watts
D1977 watts

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

SelectAnswer
A4
B3
C1
D7

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

SelectAnswer
A300 ohms
B50 ohms
C450 ohms
D72 ohms

45. - E9D12

Which of the following would provide the best RF ground for your station?

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

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

SelectAnswer
AConnect a parallel-resonant LC network across the antenna feed terminals
BUse a 50 ohm 1:1 balun between the antenna and feed line
CUse the universal stub matching technique
DConnect a series-resonant LC network across the antenna feed terminals

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

SelectAnswer
A15 meters
B20 meters
C71 meters
D10 meters

48. - E9G08

What is the process of normalization with regard to a Smith chart?

SelectAnswer
AReassigning prime center with regard to the reactance axis
BReassigning impedance values with regard to the prime center
CReassigning reactance values with regard to the resistance axis
DReassigning resistance values with regard to the reactance axis

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

SelectAnswer
AIt eliminates tracking errors caused by strong out-of-band signals
BIt is electro statically balanced against ground, giving better nulls
CIt allows stations to communicate without giving away their position
DIt automatically cancels ignition noise in mobile installations

50. - E0A08

What does SAR measure?

SelectAnswer
AThe rate at which RF energy is absorbed by the body
BThe rate of RF energy reflected from stationary terrain
CSynthetic Aperture Ratio of the human body
DSignal Amplification Rating

Figure E6-5

Figure E7-1

Figure E7-3

Figure E9-2