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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
A1 kHz above the lower band edge
B300 Hz above the lower band edge
CThe exact lower band edge
D3 kHz above the lower band edge

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

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

SelectAnswer
AOnly earth stations, repeater stations or model craft
BOnly beacon, repeater or space stations
COnly auxiliary, beacon or space stations
DOnly auxiliary, repeater or space stations

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

SelectAnswer
AOnly General, Advanced or Amateur Extra Class
BAll except Technician Class
COnly Amateur Extra Class
DAny class with appropriate operator privileges

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

SelectAnswer
ASend the application form to the FCC and inform the FCC of the grade
BDestroy the application form
CReturn the application document to the examinee
DMaintain the application form with the VEC's records

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 provide for experimental amateur communications
CTo provide additional spectrum for personal use
DTo allow regular operation on Land Mobile channels

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

SelectAnswer
A50.0 MHz - 50.2 MHz
B435 MHz - 438 MHz
C29.5 MHz - 29.7 MHz
D144 MHz - 146 MHz

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

SelectAnswer
AFrequency modulation of the video carrier
BAll of these choices are correct
CA separate VHF or UHF audio link
DFrequency-modulated sub-carrier

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

SelectAnswer
AAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
BThe acceptable practice of manually posting the call signs of stations on a spotting network
CA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
DThe generally prohibited practice of posting one's own call sign and frequency on a spotting network

10. - E2D14

What is one advantage of using JT65 coding?

SelectAnswer
AEasily copied by ear if necessary
BUses only a 65 Hz bandwidth
CThe ability to decode signals which have a very low signal to noise ratio
DPermits fast-scan TV transmissions over narrow bandwidth

11. - E2E08

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

SelectAnswer
AAMTOR
BHellschreiber
CRTTY
DPACTOR

12. - E3A15

What is an electromagnetic wave?

SelectAnswer
AA wave consisting of an electric field and a magnetic field oscillating at right angles to each other
BA wave consisting of two electric fields at parallel right angles to each other
CA wave consisting of two magnetic fields at right angles to each other
DA wave of alternating current, in the core of an electromagnet

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

SelectAnswer
AAround sunrise
BAny time
CEarly evening
DAround sunset

14. - E3C11

What does VOACAP software model?

SelectAnswer
AAC current and impedance
BAC voltage and impedance
CHF propagation
DVHF radio propagation

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

SelectAnswer
ASWR and time
BSWR and frequency
CRF amplitude and time
DRF amplitude and frequency

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A165.2 Hz
B1.4652 MHz
C146.52 Hz
D14.652 kHz

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

SelectAnswer
A-174 dBm
B-148 dBm
C-164 dBm
D-155 dBm

18. - E4D08

What causes intermodulation in an electronic circuit?

SelectAnswer
APositive feedback
BToo little gain
CLack of neutralization
DNonlinear circuits or devices

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

SelectAnswer
ABroadband white noise
BPower line noise
CAll of these choices are correct
DIgnition noise

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 multiplied by the resistance
DReactance of either the inductance or capacitance divided by the resistance

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

SelectAnswer
A14 degrees with the voltage lagging the current
B14 degrees with the voltage leading the current
C76 degrees with the voltage leading the current
D76 degrees with the voltage lagging the current

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

SelectAnswer
ANear field diagram
BPhasor diagram
CFar field diagram
DVenn diagram

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
C0.866
D1.73

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

SelectAnswer
A2
B1
C6
D3

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

SelectAnswer
AIt has the high input impedance of CMOS and the low output impedance of bipolar transistors
BIts simplicity results in much less expensive devices than standard CMOS
CAll of these choices are correct
DIt is totally immune to electrostatic damage

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

SelectAnswer
ASnubber capacitor
BTrimmer capacitor
CClipper capacitor
DFeedback capacitor

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

SelectAnswer
ALow leakage doubly insulated package
BTwo chips in each package (Dual In Package)
CPackage mounts in a direct inverted position
DA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

SelectAnswer
ACadmium Sulfide
BCopper oxide
CSilicon
DSelenium

30. - E7A07

What logical operation does a NAND gate perform?

SelectAnswer
AIt produces logic "0" at its output only when all inputs are logic "1"
BIt produces logic "1" at its output only when all inputs are logic "1"
CIt produces logic "0" at its output only when all inputs are logic "0"
DIt produces logic "0" at its output if some but not all inputs are logic "1"

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

SelectAnswer
AThe power transistor is at saturation or cut off most of the time, resulting in low power dissipation
BSwitching amplifiers operate at higher voltages
CSwitching amplifiers use push-pull circuits
DLinear amplifiers have high gain resulting in higher harmonic content

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

SelectAnswer
AA network with only three discrete parts
BA Phase Inverter Load network
CA Pi-network with an additional series inductor on the output
DA matching network in which all components are isolated from ground

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

SelectAnswer
AOutput voltage multiplied by output current
BVoltage difference from input to output multiplied by output current
CInput voltage multiplied by input current
DInput voltage divided by output current

34. - E7E11

Which type of detector is used for demodulating SSB signals?

SelectAnswer
APhase detector
BPhase comparator
CDiscriminator
DProduct detector

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

SelectAnswer
A8 bits
B10 bits
C4 bits
D6 bits

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H11

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

SelectAnswer
ASpurious signals at discrete frequencies
BDigital conversion noise
CBroadband noise
DNyquist limit noise

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

SelectAnswer
ABy measuring the heating effect in a known resistor
BBy using an absorption wave meter
CBy measuring the voltage with a D'Arsonval meter
DBy using a grid dip meter

39. - E8B11

What is digital time division multiplexing?

SelectAnswer
ATwo or more signals are quadrature modulated to increase bandwidth efficiency
BTwo or more data streams share the same channel by transmitting time of transmission as the sub-carrier
CTwo or more signals are arranged to share discrete time slots of a data transmission
DTwo or more data streams are assigned to discrete sub-carriers on an FM transmitter

40. - E8C10

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

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

41. - E8D10

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

SelectAnswer
ABaudot 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
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 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

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

SelectAnswer
A420 watts
B78.7 watts
C286 watts
D1977 watts

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

SelectAnswer
A75 degrees
B7.5 degrees
C25 degrees
D45 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. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

SelectAnswer
AGain does not change
BGain increases by 6 dB
CGain increases by 3 dB
DGain is multiplied by 0.707

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

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AVery high impedance
BVery low impedance
CThe same as the output impedance of the generator
DThe same as the characteristic impedance of the line

48. - E9G05

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

SelectAnswer
AAzimuth angle radiation pattern chart
BElevation angle radiation pattern chart
CFree space radiation directivity chart
DSmith chart

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

SelectAnswer
AIt is electro statically balanced against ground, giving better nulls
BIt eliminates tracking errors caused by strong out-of-band signals
CIt allows stations to communicate without giving away their position
DIt automatically cancels ignition noise in mobile installations

50. - E0A01

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

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

Figure E6-2

Figure E9-2

Figure E9-3