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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

SelectAnswer
A60 Hz
B2.8 kHz
C170 Hz
D1.5 kHz

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 of geographical or horticultural importance
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 in an ITU Zone designated for coordination with one or more foreign governments

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

SelectAnswer
ACommunications incidental to the purpose of the amateur service and remarks of a personal nature
BAll of these choices are correct
CBusiness-related messages for non-profit organizations
DMessages intended for connection to users of the maritime satellite service

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

5. - E1E08

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

SelectAnswer
AFriends of the VE
BRelatives of the VE as listed in the FCC rules
CEmployees of the VE
DAll of these choices are correct

6. - E1F09

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

SelectAnswer
AThe transmission must not be used to obscure the meaning of any communication
BAll of these choices are correct
CA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
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
ALEO
BGeostationary
CHEO
DGeomagnetic

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

SelectAnswer
AHue
BLuminance
CChroma
DSpectral Intensity

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

SelectAnswer
A6 m
B33 cm
C2 m
D30 m

10. - E2D05

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

SelectAnswer
ANode hopping
BStore-and-forward
CDigipeating
DMulti-satellite relaying

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
AYour transmit frequency is incorrect
BAnother station you are unable to hear is using the frequency
CAll of these choices are correct
DThe protocol version you are using is not the supported by the digital station

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. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

SelectAnswer
A20 meters
B6 meters
C80 meters
D10 meters

14. - E3C11

What does VOACAP software model?

SelectAnswer
AVHF radio propagation
BAC current and impedance
CAC voltage and impedance
DHF propagation

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

SelectAnswer
AA Q meter
BA spectrum analyzer
CAn ohmmeter
DAn antenna analyzer

16. - E4B11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

SelectAnswer
ALoosely couple the analyzer near the antenna base
BConnect the antenna feed line directly to the analyzer's connector
CConnect the analyzer via a high-impedance transformer to the antenna
DLoosely couple the antenna and a dummy load to the analyzer

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

SelectAnswer
AOne-half the maximum sampling buffer size
BOne-half the maximum sample rate
CThe maximum count value of the analog-to-digital converter
DThe reference voltage of the analog-to-digital converter

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

SelectAnswer
AThe difference in dB between the noise floor and the third order intercept point
BThe difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
CThe minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
DThe minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

SelectAnswer
AThe broadcast station is transmitting an over-modulated signal
BYour station receiver IF amplifier stage is defective
CNearby corroded metal joints are mixing and re-radiating the broadcast signals
DYou are receiving sky wave signals from a distant station

20. - E5A10

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

SelectAnswer
AResistance divided by the reactance of either the inductance or capacitance
BReactance of the inductance times the reactance of the capacitance
CReactance of either the inductance or capacitance divided by the resistance
DReactance of either the inductance or capacitance times 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
AA discharge factor of one
BOne discharge period
CAn exponential discharge rate of one
DOne time constant

22. - E5C10

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

SelectAnswer
AThe sum of the reactive and resistive components
BResistive component
CReactive component
DThe difference between the resistive and reactive components

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
A80 watts
B400 watts
C50 watts
D2000 watts

24. - E6A01

In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?

SelectAnswer
AIn microwave circuits
BIn high-power audio circuits
CIn high-current rectifier circuits
DIn very low frequency RF circuits

25. - E6B03

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

SelectAnswer
APoint contact
BJunction
CTunnel
DZener

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

SelectAnswer
A5
B6
C4
D2

27. - E6D13

What is the primary cause of inductor self-resonance?

SelectAnswer
AInductive kickback
BThe skin effect
CNon-linear core hysteresis
DInter-turn capacitance

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

SelectAnswer
AIts phase shift changes rapidly with frequency
BIt is used in a battery charger circuit
CIt samples an analog signal and passes it in stages from the input to the output
DIt is a CMOS analog-to-digital converter

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

SelectAnswer
AOptoisolators provide a low impedance link between a control circuit and a power circuit
BOptoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
COptoisolators eliminate the effects of reflected light in the control circuit
DOptoisolators provide impedance matching between the control circuit and power circuit

30. - E7A02

What is the function of a decade counter digital IC?

SelectAnswer
AIt produces one output pulse for every ten input pulses
BIt adds two decimal numbers together
CIt decodes a decimal number for display on a seven segment LED display
DIt produces ten output pulses for every input pulse

31. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

SelectAnswer
ATune the stage for maximum SWR
BTune both the input and output for maximum power
CInstall parasitic suppressors and/or neutralize the stage
DUse a phase inverter in the output filter

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

SelectAnswer
AMeteor scatter
BDigital
CVideo
DSingle-Sideband voice

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

34. - E7E10

How does a diode detector function?

SelectAnswer
ABy breakdown of the Zener voltage
BBy mixing signals with noise in the transition region of the diode
CBy rectification and filtering of RF signals
DBy sensing the change of reactance in the diode with respect to frequency

35. - E7F08

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

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

36. - E7G08

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

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

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

SelectAnswer
ASpurious signals at discrete frequencies
BDigital conversion noise
CNyquist limit noise
DBroadband noise

38. - E8A08

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

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

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

SelectAnswer
A0.47
B47
C0.214
D2.14

40. - E8C11

What is the relationship between symbol rate and baud?

SelectAnswer
ASymbol rate is only used for packet-based modes
BBaud is twice the symbol rate
CBaud is only used for RTTY
DThey are the same

41. - E8D05

What is the most common method of reducing key clicks?

SelectAnswer
ALow-pass filters at the transmitter output
BIncrease keying waveform rise and fall times
CReduce keying waveform rise and fall times
DHigh-pass filters at the transmitter output

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

SelectAnswer
ADistance from the transmitter
BSoil conductivity
CTake-off angle
DThe standing wave ratio

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

SelectAnswer
A3 dB
B15 dB
C28 dB
D24 dB

44. - E9C07

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

SelectAnswer
A450 ohms
B300 ohms
C50 ohms
D72 ohms

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

SelectAnswer
ANo change occurs
BIt becomes flat
CIt is decreased
DIt is increased

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 omega matching system
CThe delta 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
ASmaller reflection coefficient
BLower velocity factor
CHigher SWR
DLower loss

48. - E9G03

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

SelectAnswer
ABeam headings and radiation patterns
BTrigonometric functions
CImpedance and SWR values in transmission lines
DSatellite azimuth and elevation bearings

49. - E9H11

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

SelectAnswer
AA very sharp peak
BA very sharp single null
CBroad band response
DHigh-radiation angle

50. - E0A01

What is the primary function of an external earth connection or ground rod?

SelectAnswer
AReduce RF current flow between pieces of equipment
BReduce RFI to telephones and home entertainment systems
CLightning protection
DReduce received noise

Figure E6-5

Figure E9-2