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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
A300 Hz above the lower band edge
BThe exact lower band edge
C1 kHz above the lower band edge
D3 kHz above the lower band edge

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

3. - E1C02

What is meant by automatic control of a station?

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

4. - E1D01

What is the definition of the term telemetry?

SelectAnswer
AOne-way transmission that initiates, modifies, or terminates the functions of a device at a distance
BOne-way transmission of measurements at a distance from the measuring instrument
CTwo-way radiotelephone transmissions in excess of 1000 feet
DTwo-way single channel transmissions of data

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

SelectAnswer
ANo expenses are authorized for reimbursement
BProviding amateur operator license examination preparation training materials
CTeaching an amateur operator license examination preparation course
DPreparing, processing, administering and coordinating an examination for an amateur radio license

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

SelectAnswer
A1.5 kW
B1.5 W
C10 W
D1 W

7. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

SelectAnswer
AAll of these choices are correct
BFM and CW
CSSB and SSTV
DPSK and Packet

8. - E2B15

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

SelectAnswer
AA two-tone signal
BSpecific tone amplitudes
CSpecific tone frequencies
DElapsed time

9. - E2C05

What is the function of a DX QSL Manager?

SelectAnswer
ATo allocate frequencies for DXpeditions
BTo relay calls to and from a DX station
CTo run a net to allow many stations to contact a rare DX station
DTo handle the receiving and sending of confirmation cards for a DX station

10. - E2D08

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

SelectAnswer
AAcknowledgement
BConnect
CDisconnect
DUnnumbered Information

11. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

SelectAnswer
ARTTY
BHellschreiber
CPACTOR
DAMTOR

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

SelectAnswer
AWind shear
BDust devil
CTemperature inversion
DThe jet stream

13. - E3B10

What is the cause of gray-line propagation?

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

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

SelectAnswer
AD-region skip
BDownward bending due to aurora refraction
CE-region skip
DDownward bending due to density variations in the atmosphere

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

SelectAnswer
AQ of the interface of the interface circuit
BAmount of memory on the soundcard
CAll of these choices are correct
DAnalog-to-digital conversion speed of the soundcard

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

SelectAnswer
ALow reluctance input
BHigh impedance input
CHigh reluctance input
DLow impedance input

17. - E4C01

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

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

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

SelectAnswer
AOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
BOscillator instability and severe audio distortion of all but the strongest received signals
CCross-modulation of the desired signal and insufficient audio power to operate the speaker
DCross-modulation of the desired signal and desensitization from strong adjacent signals

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

SelectAnswer
AA whining type noise that continually pulses off and on
BThe appearance of unstable modulated or unmodulated signals at specific frequencies
CA loud AC hum in the audio output of your station receiver
DA clicking noise at intervals of a few seconds

20. - E5A13

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

SelectAnswer
AParasitic effects are minimized
BPhase shift can become uncontrolled
CFewer components are needed for the same performance
DInternal voltages and circulating currents increase

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

SelectAnswer
AVoltage and current are 180 degrees out of phase
BVoltage and current are in phase
CVoltage leads current by 90 degrees
DCurrent leads voltage by 90 degrees

22. - E5C01

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

SelectAnswer
A-jX
BX
C+jX
DOmega

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

SelectAnswer
A1.414
B0.5
C1.73
D0.866

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

SelectAnswer
A5
B2
C4
D6

25. - E6B08

Which of the following describes a type of semiconductor diode?

SelectAnswer
ACMOS-field effect
BThermionic emission diode
CElectrolytic rectifier
DMetal-semiconductor junction

26. - E6C07

What best describes a pull-up or pull-down resistor?

SelectAnswer
AA resistor in a keying circuit used to reduce key clicks
BA resistor that insures that an oscillator frequency does not drive lower over time
CA resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
DA resistor connected to an op-amp output that only functions when the logic output is false

27. - E6D05

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

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

28. - E6E02

Which of the following device packages is a through-hole type?

SelectAnswer
ASOT
BDIP
CPLCC
DBall grid array

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

SelectAnswer
AA lens and a photomultiplier
BA frequency modulated helium-neon laser
CAn amplitude modulated helium-neon laser
DAn LED and a phototransistor

30. - E7A12

What type of logic defines "0" as a high voltage?

SelectAnswer
AAssertive Logic
BReverse Logic
CNegative logic
DPositive Logic

31. - E7B11

In Figure E7-1, what is the purpose of R3?

SelectAnswer
AEmitter bypass
BSelf bias
COutput load resistor
DFixed bias

32. - E7C15

What is a crystal lattice filter?

SelectAnswer
AA power supply filter made with interlaced quartz crystals
BA filter with narrow bandwidth and steep skirts made using quartz crystals
CA filter with wide bandwidth and shallow skirts made using quartz crystals
DAn audio filter made with four quartz crystals that resonate at 1kHz intervals

33. - E7D11

What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?

SelectAnswer
APass transistor
BSwitching inductance
CError amplifier
DReference voltage

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

SelectAnswer
AMixer blanking occurs
BSpurious mixer products are generated
CA beat frequency is generated
DAutomatic limiting occurs

35. - E7F08

What is the function of decimation with regard to digital filters?

SelectAnswer
ARemoving unnecessary significant digits
BAttenuating the signal
CReducing the effective sample rate by removing samples
DConverting data to binary code decimal form

36. - E7G08

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

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

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

SelectAnswer
APierce and Zener
BColpitts and Hartley
CArmstrong and deForest
DNegative feedback and balanced feedback

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

SelectAnswer
AThe frequency of the modulating signal
BThe degree of carrier suppression
CThe amplifier gain
DThe characteristics of the modulating signal

39. - E8B10

What describes frequency division multiplexing?

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

40. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

SelectAnswer
A0.5 kHz
B1.0 kHz
C0.3 kHz
D0.1 Hz

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

SelectAnswer
A+15 dB
B+10 dB
C-20 dB
D-30 dB

42. - E9A09

How is antenna efficiency calculated?

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

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

SelectAnswer
A50 degrees
B75 degrees
C30 degrees
D25 degrees

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

SelectAnswer
AA figure-8 end-fire along the axis of the array
BA figure-8 broadside to the axis of the array
CCardioid
DOmni-directional

45. - E9D13

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

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

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

SelectAnswer
AThe stub matching system
BThe delta matching system
CThe omega matching system
DThe gamma matching system

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

SelectAnswer
ALower loss
BHigher SWR
CSmaller reflection coefficient
DLower velocity factor

48. - E9G07

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

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

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

SelectAnswer
AIt should be one or more wavelengths long
BIt should be configured as a four-sided loop
CIts overall length must not exceed 1/4 wavelength
DIt must be mounted more than 1 wavelength above ground

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

SelectAnswer
AUse an antenna modeling program to calculate field strength at accessible locations
BAll of the choices are correct
CUse a calibrated antenna analyzer
DUse a hand calculator plus Smith-chart equations to calculate the fields

Figure E6-2

Figure E7-1

Figure E9-1

Figure E9-3