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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
A60 meter band
B17 meter band
C30 meter band
D12 meter band

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

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

SelectAnswer
AYou must bring a copy of FCC Public Notice DA 11-221
BThe U.S. embassy must approve of your operation
CYou must append "/CEPT" to your call sign
DYou must identify in the official language of the country in which you are operating

4. - E1D01

What is the definition of the term telemetry?

SelectAnswer
ATwo-way radiotelephone transmissions in excess of 1000 feet
BTwo-way single channel transmissions of data
COne-way transmission that initiates, modifies, or terminates the functions of a device at a distance
DOne-way transmission of measurements at a distance from the measuring instrument

5. - E1E02

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

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

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

SelectAnswer
ATo provide temporary operation while awaiting normal licensing
BTo allow regular operation on Land Mobile channels
CTo provide additional spectrum for personal use
DTo provide for experimental amateur communications

7. - E2A01

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

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

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

SelectAnswer
A60
B1080
C525
D30

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

SelectAnswer
AA 2 meter VHF transceiver with a 1200 baud modem
BA 440 MHz transceiver with a 9600 baud modem
CA standard wireless router running custom software
DAn optical cable connection between the USB ports of 2 separate computers

10. - E2D07

What digital protocol is used by APRS?

SelectAnswer
AAX.25
BAMTOR
CPACTOR
D802.11

11. - E2E06

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

SelectAnswer
A48 baud
B110 baud
C1200 baud
D300 baud

12. - E3A06

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

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

13. - E3B05

Which amateur bands typically support long-path propagation?

SelectAnswer
A6 meters to 2 meters
B160 meters to 40 meters
C160 meters to 10 meters
D30 meters to 10 meters

14. - E3C11

What does VOACAP software model?

SelectAnswer
AAC current and impedance
BAC voltage and impedance
CVHF radio propagation
DHF propagation

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ABit error rate tester
BModulation monitor
CLogic analyzer
DNetwork analyzer

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

SelectAnswer
A75 watts
B25 watts
C100 watts
D125 watts

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

SelectAnswer
A15.210 MHz
B13.845 MHz
C14.755 MHz
D14.445 MHz

18. - E4D13

Which of the following can cause receiver desensitization?

SelectAnswer
AStrong adjacent channel signals
BAudio gain adjusted too low
CSquelch gain misadjusted
DAudio bias adjusted too high

19. - E4E06

What is a major cause of atmospheric static?

SelectAnswer
AThunderstorms
BMeteor showers
CSolar radio frequency emissions
DGeomagnetic storms

20. - E5A16

What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?

SelectAnswer
A23.5 MHz
B7.12 MHz
C23.5 kHz
D7.12 kHz

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

SelectAnswer
A220 seconds
B110 seconds
C440 seconds
D55 seconds

22. - E5C12

If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?

SelectAnswer
AIt contains resistance and inductive reactance
BIt contains resistance and capacitive reactance
CIt has to be a direct current circuit
DIt is equivalent to a pure resistance

23. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

SelectAnswer
A50 watts
B400 watts
C2000 watts
D80 watts

24. - E6A06

What is the beta of a bipolar junction transistor?

SelectAnswer
AThe frequency at which the current gain is reduced to 1
BThe change in collector current with respect to base current
CThe switching speed of the transistor
DThe breakdown voltage of the base to collector junction

25. - E6B13

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

SelectAnswer
AForward bias
BReverse bias
CZero bias
DInductive bias

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
ADifferential output capability
BLower power consumption
CLower distortion
DImmune to damage from static discharge

27. - E6D08

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

SelectAnswer
APowdered-iron cores generally have greater initial permeability
BPowdered-iron cores use smaller diameter wire for the same inductance
CPowdered-iron cores generally maintain their characteristics at higher currents
DPowdered-iron cores generally require fewer turns to produce a given inductance

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

SelectAnswer
AThe ability to retrieve information from a single signal even in the presence of other strong signals
BNearly infinite gain, very high input impedance, and very low output impedance
CPlate current that is controlled by a control grid
DControlled gain, low noise figure, and constant input and output impedance over the specified frequency range

29. - E6F01

What is photoconductivity?

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

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

SelectAnswer
AA multiplexer
BAn XOR gate
CA flip-flop
DAn OR gate

31. - E7B02

What is a Class D amplifier?

SelectAnswer
AA frequency doubling amplifier
BA type of amplifier that uses switching technology to achieve high efficiency
CA low power amplifier that uses a differential amplifier for improved linearity
DAn amplifier that uses drift-mode FETs for high efficiency

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
ALower losses
BHigher efficiency
CGreater transformation range
DGreater harmonic suppression

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

SelectAnswer
AMatching of day and night charge rates
BPrevention of battery damage due to overcharge
CPrevention of battery undercharge
DControl of electrolyte levels during battery discharge

34. - E7E01

Which of the following can be used to generate FM phone emissions?

SelectAnswer
AA balanced modulator on the audio amplifier
BA reactance modulator on the final amplifier
CA balanced modulator on the oscillator
DA reactance modulator on the oscillator

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

SelectAnswer
AAt the same rate as the highest frequency component of the signal
BAt twice the rate of the highest frequency component of the signal
CAt half the rate of the highest frequency component of the signal
DAt four times the rate of the highest frequency component of the signal

36. - E7G03

What is the typical input impedance of an integrated circuit op-amp?

SelectAnswer
AVery high
BVery low
C1000 ohms
D100 ohms

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a quartz crystal
CThrough link coupling
DThrough a neutralizing capacitor

38. - E8A09

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

SelectAnswer
A256 divided by the gain of the input amplifier
B256
C8 multiplied by the gain of the input amplifier
D8

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
A3
B1000
C0.3
D3000

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

SelectAnswer
AIt has more possible states than simple binary
BIt increases security
CIt has more resolution than simple binary
DIt facilitates error detection

41. - E8D04

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

SelectAnswer
AThe generation of key clicks
BLimits data speed
CThe generation of RF harmonics
DMore difficult to copy

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

SelectAnswer
ATo calculate the front-to-side ratio of the antenna
BTo match impedances in order to minimize standing wave ratio on the transmission line
CTo calculate the front-to-back ratio of the antenna
DTo measure the near-field radiation density from a transmitting antenna

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
BElement spacing limits could be exceeded
CThe gain may change depending on frequency
DThe E-field and H-field patterns may reverse

44. - E9C10

Which of the following describes a Zepp antenna?

SelectAnswer
AA dipole constructed from zip cord
BAn end fed dipole antenna
CAn omni-directional antenna commonly used for satellite communications
DA vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

SelectAnswer
AArrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
BStack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
CArrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
DStack two Yagis fed in phase to form an array with the respective elements in parallel planes

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

SelectAnswer
ATo provide DC isolation between the feed line and the antenna
BTo transform the antenna impedance to a higher value
CTo cancel the inductive reactance of the matching network
DTo provide a rejection notch that prevents the radiation of harmonics

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AThe same as the input impedance to the final generator stage
BA capacitive reactance
CThe same as the characteristic impedance of the line
DAn inductive reactance

48. - E9G05

What type of chart is shown in Figure E9-3?

SelectAnswer
AAzimuth angle radiation pattern chart
BFree space radiation directivity chart
CElevation angle radiation pattern chart
DSmith chart

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
CIt must be mounted more than 1 wavelength above ground
DIts overall length must not exceed 1/4 wavelength

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

SelectAnswer
ABlood clotting from the intense magnetic field
BLocalized heating of the body from RF exposure in excess of the MPE limits
CIngestion of ozone gas from the cooling system
DHearing loss caused by high voltage corona discharge

Figure E9-3