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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

SelectAnswer
AThe control operator of the originating station
BThe control operators of all the stations in the system not authenticating the source from which they accept communications
CThe control operator of the packet bulletin board station
DThe control operators of all the stations in the system

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

SelectAnswer
ANo special rules apply if your antenna structure will be less than 300 feet in height
BYou must file an Environmental Impact Statement with the EPA before construction begins
CYou must obtain a construction permit from the airport zoning authority
DYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules

3. - E1C02

What is meant by automatic control of a station?

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

4. - E1D06

Which of the following is a requirement of a space station?

SelectAnswer
AThe space station must be capable of terminating transmissions by telecommand when directed by the FCC
BAll of these choices are correct
CThe space station must be capable of changing its orbit whenever such a change is ordered by NASA
DThe space station must cease all transmissions after 5 years

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

SelectAnswer
AAll of these choices are correct
BRevocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
CA sentence of up to one year in prison
DA fine of up to $1000 per occurrence

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

SelectAnswer
AAll of these choices are correct
BA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
CThe transmission must not be used to obscure the meaning of any communication
DThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions

7. - E2A13

What type of satellite appears to stay in one position in the sky?

SelectAnswer
AGeostationary
BHEO
CLEO
DGeomagnetic

8. - E2B06

What is vestigial sideband modulation?

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

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

SelectAnswer
AIn the middle of each band, usually on the national calling frequency
BIn the middle of the band, usually 25 kHz above the national calling frequency
CIn the weak signal segment of the band, with most of the activity near the calling frequency
DAt the top of each band, usually in a segment reserved for contests

10. - E2D05

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

SelectAnswer
AStore-and-forward
BMulti-satellite relaying
CNode hopping
DDigipeating

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

SelectAnswer
AAll of these choices are correct
BThe protocol version you are using is not the supported by the digital station
CYour transmit frequency is incorrect
DAnother station you are unable to hear is using the frequency

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

SelectAnswer
AThe F1 layer
BThe D layer
CThe F2 layer
DThe E layer

13. - E3B03

What is the best time of day for transequatorial propagation?

SelectAnswer
ANoon
BLate at night
CAfternoon or early evening
DMorning

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

SelectAnswer
ATwice as great
B50 percent greater
C10 percent greater
DFour times as great

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

SelectAnswer
AFalse triggering occurs
BAll signals will have a DC offset
CFalse signals are displayed
DCalibration of the vertical scale is no longer valid

16. - E4B07

What do the subscripts of S parameters represent?

SelectAnswer
ARelative quality of the data
BFrequency order of the measurements
CThe relative time between measurements
DThe port or ports at which measurements are made

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

SelectAnswer
ACross-modulation interference
BDesensitization
CCapture effect
DFrequency discrimination

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

SelectAnswer
AThird-order intermodulation produces three products for every input signal within the band of interest
BThe third-order product of two signals which are in the band of interest is also likely to be within the band
CThird-order products are an indication of poor image rejection
DThe third-order intercept is much higher than other orders

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

SelectAnswer
AReceived audio in the speech range might have an echo effect
BFM signals can no longer be demodulated
CThe audio frequency bandwidth of the received signal might be compressed
DNearby signals may appear to be excessively wide even if they meet emission standards

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

SelectAnswer
AResistance divided by the reactance of either the inductance or capacitance
BReactance of the inductance multiplied by the reactance of the capacitance
CReactance of either the inductance or capacitance divided by the resistance
DReactance of either the inductance or capacitance multiplied by the resistance

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

SelectAnswer
AOne time constant
BA discharge factor of one
CAn exponential discharge rate of one
DOne discharge period

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

SelectAnswer
AA negative real part
BA positive phase angle
CA negative phase angle
DA positive real part

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
A2000 watts
B80 watts
C400 watts
D50 watts

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
ACorner frequency
BAlpha cutoff frequency
CBeta cutoff frequency
DAlpha rejection frequency

25. - E6B06

Which of the following is a common use of a hot-carrier diode?

SelectAnswer
AAs a constant voltage reference in a power supply
BAs a VHF/UHF mixer or detector
CAs a variable capacitance in an automatic frequency control circuit
DAs balanced mixers in FM generation

26. - E6C03

What is tri-state logic?

SelectAnswer
ALow power logic devices designed to operate at 3 volts
BProprietary logic devices manufactured by Tri-State Devices
CLogic devices that utilize ternary math
DLogic devices with 0, 1, and high impedance output states

27. - E6D14

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

SelectAnswer
ABrass
BPowdered-iron
CCeramic
DFerrite

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

SelectAnswer
ATo provide a low-pass frequency response
BHigh-voltage insulating ability
CEnhanced sensitivity to light
DBetter dissipation of heat

29. - E6F01

What is photoconductivity?

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

30. - E7A01

Which is a bi-stable circuit?

SelectAnswer
AA clock
BAn "OR" gate
CAn "AND" gate
DA flip-flop

31. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

SelectAnswer
ALoad resistors
BFeedback
CSelf bias
DFixed bias

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

SelectAnswer
AA filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
BA variable bandwidth crystal lattice filter
CAn automatic notch filter
DA special filter that emphasizes image responses

33. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

SelectAnswer
AIt uses a diode bridge rectifier for increased output
BIt uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle
CThe inverter design does not require any output filtering
DThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output

34. - E7E09

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

SelectAnswer
AAutomatic limiting occurs
BSpurious mixer products are generated
CMixer blanking occurs
DA beat frequency is generated

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

SelectAnswer
AQuadrature mixing
BSignal conditioning
CFast Fourier Transform
DDecimation

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic circuit also known as a monostable multivibrator
BAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
CAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
DAn electronic circuit consisting of a precision push-pull amplifier with a differential input

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AVery low power consumption decreases frequency drift
BVery high speed allows digitizing high frequencies
CAll of these choices are correct
DImmunity to out of sequence coding reduces spurious responses

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
A0.6
B0.167
C60
D1.67

40. - E8C01

How is Forward Error Correction implemented?

SelectAnswer
ABy the receiving station repeating each block of three data characters
BBy transmitting a special algorithm to the receiving station along with the data characters
CBy varying the frequency shift of the transmitted signal according to a predefined algorithm
DBy transmitting extra data that may be used to detect and correct transmission errors

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
BBaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
CBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
DBaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

SelectAnswer
AIt decreases
BIt increases arithmetically
CIt is essentially unaffected
DIt increases geometrically

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

SelectAnswer
AAzimuth
BPolarization
CRadiation resistance
DElevation

44. - E9C11

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

SelectAnswer
AThe low-angle radiation increases
BBoth the high-angle and low-angle radiation decrease
CThe high-angle radiation increases
DThe low-angle radiation decreases

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

SelectAnswer
AIt must be neutralized
BIt is too sharply directional at lower frequencies
CIt might radiate harmonics
DIt radiates the harmonics and fundamental equally well

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

SelectAnswer
AIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
BIt allows single-band antennas to operate on other bands
CIt ensures that each driven element operates in concert with the others to create the desired antenna pattern
DIt makes sure the antenna has a low-angle radiation pattern

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

SelectAnswer
AFoam dielectric has higher velocity factor
BFoam dielectric has lower safe operating voltage limits
CFoam dielectric has lower loss per unit of length
DAll of these choices are correct

48. - E9G03

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

SelectAnswer
AImpedance and SWR values in transmission lines
BSatellite azimuth and elevation bearings
CBeam headings and radiation patterns
DTrigonometric functions

49. - E9H11

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

SelectAnswer
AA very sharp single null
BA very sharp peak
CHigh-radiation angle
DBroad band response

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

SelectAnswer
AMake sure signals from your station are less than the controlled MPE limits
BMake sure signals from your station are less than the uncontrolled MPE limits
CYou need only evaluate exposure levels on your own property
DAdvise your neighbors of the results of your tests

Figure E7-1

Figure E9-2