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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

SelectAnswer
AYes, the displayed frequency is within the 80 meter CW band segment
BNo, U.S. stations are not permitted to use CW emissions below 3.525 MHz
CYes, the DX station initiated the contact
DNo, one of the sidebands of the CW signal will be out of the 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
BAn Environmental Assessment must be submitted to the FCC
CA letter of intent must be filed with the National Audubon Society
DA form FSD-15 must be submitted to the Department of the Interior

3. - E1C04

What is meant by IARP?

SelectAnswer
AAn indication of increased antenna reflected power
BA forecast of intermittent aurora radio propagation
CThe internal amateur radio practices policy of the FCC
DAn international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

SelectAnswer
A2 meters and 1.25 meters
B2 meters
C6 meters and 2 meters
D6 meters, 2 meters, and 1.25 meters

5. - E1E12

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

SelectAnswer
AMaintain the application form with the VEC's records
BReturn the application document to the examinee
CDestroy the application form
DSend the application form to the FCC and inform the FCC of the grade

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. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

SelectAnswer
AAn isotropic antenna
BA log-periodic dipole array
CA linearly polarized antenna
DA circularly polarized antenna

8. - E2B02

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

SelectAnswer
A60
B30
C1080
D525

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. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
ADisconnect
BConnect
CUnnumbered Information
DAcknowledgement

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

SelectAnswer
AFatal Error Correction
BForward Error Correction
CFirst Error Correction
DFinal Error Correction

12. - E3A13

Which emission mode is best for aurora propagation?

SelectAnswer
ASSB
BFM
CRTTY
DCW

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A2500 miles
B1000 miles
C7500 miles
D5000 miles

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

SelectAnswer
AIt decreases
BIt stays the same
CIt increases
DIt peaks at roughly 14 MHz

15. - E4A06

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

SelectAnswer
ACalibration of the vertical scale is no longer valid
BFalse triggering occurs
CFalse signals are displayed
DAll signals will have a DC offset

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
BLoosely couple the antenna and a dummy load to the analyzer
CConnect the antenna feed line directly to the analyzer's connector
DConnect the analyzer via a high-impedance transformer to the antenna

17. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?

SelectAnswer
AImproved receiver noise figure
BFewer components in the receiver
CReduced drift
DEasier for front-end circuitry to eliminate image responses

18. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

SelectAnswer
ADesensitization
BCross-modulation interference
CSquelch gain rollback
DQuieting

19. - E4E06

What is a major cause of atmospheric static?

SelectAnswer
AThunderstorms
BSolar radio frequency emissions
CMeteor showers
DGeomagnetic storms

20. - E5A15

Which of the following can increase Q for inductors and capacitors?

SelectAnswer
ALower losses
BHigher self-resonant frequency
CLower self-resonant frequency
DLower reactance

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

SelectAnswer
AThe susceptance phase angle is the inverse of the reactance phase angle
BIt is shifted by 90 degrees
CThe sign is reversed
DIt is unchanged

22. - E5C04

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

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

23. - E5D05

Which parasitic characteristic increases with conductor length?

SelectAnswer
APermeability
BPermittivity
CMalleability
DInductance

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

SelectAnswer
ABipolar
BP-type
CInsulated gate
DN-type

25. - E6B03

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

SelectAnswer
APoint contact
BTunnel
CZener
DJunction

26. - E6C01

What is the function of hysteresis in a comparator?

SelectAnswer
ATo cause the output to change states continually
BTo increase the sensitivity
CTo prevent input noise from causing unstable output signals
DTo allow the comparator to be used with AC input signal

27. - E6D08

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

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

28. - E6E12

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

SelectAnswer
AEnhanced sensitivity to light
BTo provide a low-pass frequency response
CHigh-voltage insulating ability
DBetter dissipation of heat

29. - E6F05

Which describes an optical shaft encoder?

SelectAnswer
AA device for generating RTTY signals by means of a rotating light source
BA device which measures the strength of a beam of light using analog to digital conversion
CA device which detects rotation of a control by interrupting a light source with a patterned wheel
DA digital encryption device often used to encrypt spacecraft control signals

30. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
APositive Logic
BAssertive Logic
CNegative logic
DReverse Logic

31. - E7B02

What is a Class D amplifier?

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

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

SelectAnswer
ACascode
BPi
CPi-L
DOmega

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

SelectAnswer
AA shunt current source
BA shunt regulator
CA series current source
DA series regulator

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
CMixer blanking occurs
DAutomatic limiting occurs

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
AA switching mixer is used to generate I and Q signals directly from the RF input
BSoftware is converted from source code to object code during operation of the receiver
CIncoming RF is converted to a control voltage for a voltage controlled oscillator
DIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A7
B14
C0.07
D28

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

SelectAnswer
AA direct digital synthesizer
BA hybrid synthesizer
CA diode-switching matrix synthesizer
DA phase locked loop synthesizer

38. - E8A04

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

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

39. - E8B10

What describes frequency division multiplexing?

SelectAnswer
AThe transmitted signal jumps from band to band at a predetermined rate
BTwo or more information streams are merged into a baseband, which then modulates the transmitter
CTwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
DThe transmitted signal is divided into packets of information

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

SelectAnswer
AExcess 3 code
BGray code
CExtended Binary Coded Decimal Interchange Code
DBinary Coded Decimal Code

41. - E8D10

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

SelectAnswer
ABaudot 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
BBaudot 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
CBaudot 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
DBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A14

What is meant by the radiation resistance of an antenna?

SelectAnswer
AThe resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
BThe combined losses of the antenna elements and feed line
CThe specific impedance of the antenna
DThe value of a resistance that would dissipate the same amount of power as that radiated from an antenna

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

SelectAnswer
AThey are the same
BThe radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
CThe total amount of radiation from the directional antenna is increased by the gain of the antenna
DThe total amount of radiation from the directional antenna is stronger by its front-to-back ratio

44. - E9C09

What is a G5RV antenna?

SelectAnswer
AA phased array antenna consisting of multiple loops
BA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
CA multi-band trap antenna
DA wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
AA resistive wire, such as spark plug wire
BA wide flat copper strap
CA cable with six or seven 18 gauge conductors in parallel
DA single 12 gauge or 10 gauge stainless steel wire

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. - E9F14

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

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

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

SelectAnswer
ACoaxial-length circles
BStanding wave ratio circles
CRadiation-pattern circles
DAntenna-length circles

49. - E9H11

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

SelectAnswer
ABroad band response
BA very sharp peak
CA very sharp single null
DHigh-radiation angle

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

SelectAnswer
AMicrowaves often travel long distances by ionospheric reflection
BMicrowaves are ionizing radiation
CThe high gain antennas commonly used can result in high exposure levels
DThe extremely high frequency energy can damage the joints of antenna structures

Figure E7-4