Anonymous User

Hamboozler

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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

SelectAnswer
AOnly a person with an FCC Marine Radio
BOnly a person named in an amateur station license grant
CAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
DAny person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

SelectAnswer
AThe location is in an ITU Zone designated for coordination with one or more foreign governments
BThe location is of environmental importance or significant in American history, architecture, or culture
CThe location is near an area of political conflict
DThe location is of geographical or horticultural importance

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

SelectAnswer
AA control operator must be present at the control point
BA control operator need not be present at the control point
COnly Extra Class operators may be the control operator of a remote station
DRepeater and auxiliary stations may not be remotely controlled

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

SelectAnswer
AAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
BOnly those of Amateur Extra Class operators
COnly those of General, Advanced or Amateur Extra Class operators
DAny amateur station, subject to the privileges of the class of operator license held by the control operator

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 the appropriate FCC Report and Order
CIn a question pool maintained by the FCC
DIn FCC Part 97

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

SelectAnswer
AIt was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
BIt was imported from a manufacturer in another country and was certificated by that country's government
CIt was imported from a manufacturer in a country that does not require certification of RF power amplifiers
DThe equipment dealer assembled it from a kit

7. - E2A07

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

SelectAnswer
ASSB and SSTV
BAll of these choices are correct
CFM and CW
DPSK and Packet

8. - E2B02

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

SelectAnswer
A60
B30
C525
D1080

9. - E2C07

What is the Cabrillo format?

SelectAnswer
AA standard for submission of electronic contest logs
BThe most common set of contest rules
CThe rules of order for meetings between contest sponsors
DA method of exchanging information during a contest QSO

10. - E2D12

How does JT65 improve EME communications?

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

11. - E2E05

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

SelectAnswer
AMFSK
BRTTY
CPSK31
DWinlink

12. - E3A10

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

SelectAnswer
AWind shear
BThe jet stream
CDust devil
DTemperature inversion

13. - E3B13

Why is chordal hop propagation desirable?

SelectAnswer
ASignals travel faster along ionospheric chords
BAtmospheric noise is lower in the direction of chordal hop propagation
CThe signal experiences less loss along the path compared to normal skip propagation
DThe MUF for chordal hop propagation is much lower than for normal skip propagation

14. - E3C02

What is indicated by a rising A or K index?

SelectAnswer
ADecreasing disruption of the geomagnetic field
BHigher levels of solar UV radiation
CAn increase in the critical frequency
DIncreasing disruption of the geomagnetic field

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

SelectAnswer
AA time-domain reflectometer
BA logic analyzer
CA wattmeter
DA spectrum analyzer

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A146.52 kHz
B1465.20 Hz
C146.52 Hz
D10 Hz

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

SelectAnswer
ACPU register width in bits
BRAM speed used for data storage
CAnti-aliasing input filter bandwidth
DAnalog-to-digital converter sample width in bits

18. - E4D02

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

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

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

SelectAnswer
AReceived CW signals will appear to be modulated at the DSP clock frequency
BRinging in the DSP filter will completely remove the spaces between the CW characters
CA DSP filter can remove the desired signal at the same time as it removes interfering signals
DAny nearby signal passing through the DSP system will overwhelm the desired signal

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. - E5B06

What is susceptance?

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

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

SelectAnswer
APoint 5
BPoint 4
CPoint 2
DPoint 6

23. - E5D14

What is reactive power?

SelectAnswer
APower consumed in wire resistance in an inductor
BWattless, nonproductive power
CPower consumed in circuit Q
DPower lost because of capacitor leakage

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

SelectAnswer
ABeta cutoff frequency
BCorner frequency
CAlpha cutoff frequency
DAlpha rejection frequency

25. - E6B12

What is one common use for PIN diodes?

SelectAnswer
AAs a constant voltage source
BAs a constant current source
CAs a high voltage rectifier
DAs an RF switch

26. - E6C04

What is the primary advantage of tri-state logic?

SelectAnswer
ALow power consumption
BMore efficient arithmetic operations
CHigh speed operation
DAbility to connect many device outputs to a common bus

27. - E6D14

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

SelectAnswer
ACeramic
BFerrite
CBrass
DPowdered-iron

28. - E6E06

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

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

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

SelectAnswer
AIt stays the same
BIt increases
CIt becomes unstable
DIt decreases

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

SelectAnswer
AJ-K flip-flop
BMonostable multivibrator
CAstable multivibrator
DT flip-flop

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

SelectAnswer
ABecause they are relatively far in frequency from the desired signal
BBecause they are relatively close in frequency to the desired signal
CBecause they maintain the sidebands, thus causing multiple duplicate signals
DBecause they invert the sidebands causing distortion

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

SelectAnswer
AA band-pass filter
BA Pi-network filter
CAn all-pass filter
DA notch filter

33. - E7D16

When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?

SelectAnswer
ATo equalize, as much as possible, the voltage drop across each capacitor
BTo provide a minimum load current to reduce voltage excursions at light loads
CTo provide a safety bleeder to discharge the capacitors when the supply is off
DAll of these choices are correct

34. - E7E09

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

SelectAnswer
ASpurious mixer products are generated
BA beat frequency is generated
CAutomatic limiting occurs
DMixer blanking occurs

35. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

SelectAnswer
ASample width in bits
BProcessor latency
CSample rate
DSample clock phase noise

36. - E7G08

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

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

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a neutralizing capacitor
CThrough link coupling
DThrough a capacitive divider

38. - E8A04

What is "dither" with respect to analog to digital converters?

SelectAnswer
AAn error caused by irregular quantization step size
BAn abnormal condition where the converter cannot settle on a value to represent the signal
CA small amount of noise added to the input signal to allow more precise representation of a signal over time
DA method of decimation by randomly skipping samples

39. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

SelectAnswer
A60
B0.167
C0.6
D1.67

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

SelectAnswer
AIt improves carrier suppression
BThis results in the least possible transmitted bandwidth for the particular mode
CIt is easier to demodulate with a conventional, non-synchronous detector
DAll of these choices are correct

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. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

SelectAnswer
AThe settings of an antenna tuner at the transmitter
BSunspot activity and time of day
CTransmission-line length
DAntenna height, conductor length/diameter ratio and location of nearby conductive objects

43. - E9B16

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

SelectAnswer
A7
B1
C4
D3

44. - E9C12

Which of the following describes an extended double Zepp antenna?

SelectAnswer
AA portable antenna erected using two push support poles
BAn end fed folded dipole antenna
CA center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
DA wideband vertical antenna constructed from precisely tapered aluminum tubing

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

SelectAnswer
AAs low as possible on the vertical radiator
BAs close to the transmitter as possible
CNear the center of the vertical radiator
DAt a voltage node

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 stub match
DThe epsilon match

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

SelectAnswer
ADielectric materials used in the line
BThe termination impedance
CThe line length
DThe center conductor resistivity

48. - E9G02

What type of coordinate system is used in a Smith chart?

SelectAnswer
AVoltage lines and current chords
BResistance lines and reactance chords
CVoltage circles and current arcs
DResistance circles and reactance arcs

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

SelectAnswer
AIt compensates for the effects of an isotropic antenna, thereby improving directivity
BIt reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
CIt prevents receiver overload which could make it difficult to determine peaks or nulls
DIt narrows the bandwidth of the received signal to improve signal to noise ratio

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

SelectAnswer
AOnly commercial transmitters
BEach transmitter that produces 5 percent or more of its MPE limit at accessible locations
CEach transmitter operating with a duty-cycle greater than 50 percent
DOnly the most powerful transmitter

Figure E5-2

Figure E9-2