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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

SelectAnswer
AAt the lowest frequency of the channel
BAt the center frequency of the channel
CAt the highest frequency of the channel
DOn any frequency where the signal's sidebands are within the channel

2. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AAny transmitted signal that unintentionally interferes with another licensed radio station
BAn amateur station transmission made at random without the proper call sign identification
CA signal transmitted to prevent its detection by any station other than the intended recipient
DAn emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C04

What is meant by IARP?

SelectAnswer
AA forecast of intermittent aurora radio propagation
BAn indication of increased antenna reflected power
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. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

SelectAnswer
A70 cm and 33 cm
B70 cm and 13 cm
C33 cm and 13 cm
D70 cm only

5. - E1E09

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

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

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

SelectAnswer
A53 MHz - 54 MHz
B420 MHz - 430 MHz
C440 MHz - 450 MHz
D222 MHz - 223 MHz

7. - E2A13

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

SelectAnswer
AGeomagnetic
BGeostationary
CLEO
DHEO

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

SelectAnswer
ASpecific tone frequencies
BElapsed time
CA two-tone signal
DSpecific tone amplitudes

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

SelectAnswer
ASend your full call sign and grid square
BSend your full call sign once or twice
CSend only the last two letters of your call sign until you make contact
DSend the call sign of the DX station three times, the words "this is", then your call sign three times

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

SelectAnswer
A170 Hz shift, 45 baud RTTY
B300 baud packet
CPSK31
DAMTOR

11. - E2E05

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

SelectAnswer
ARTTY
BWinlink
CPSK31
DMFSK

12. - E3A04

What do Hepburn maps predict?

SelectAnswer
AProbability of tropospheric propagation
BLocations of auroral reflecting zones
CSporadic E propagation
DLikelihood of rain-scatter along cold or warm fronts

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

SelectAnswer
ALong path and short path waves
BExtraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances
CIndependent waves created in the ionosphere that are elliptically polarized
DRefracted rays and reflected waves

14. - E3C13

What type of polarization is best for ground-wave propagation?

SelectAnswer
ACircular
BHorizontal
CElliptical
DVertical

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

SelectAnswer
AA square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
BA high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
CA frequency standard is displayed and the probe is adjusted until the deflection time is accurate
DA DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

SelectAnswer
AInput attenuator accuracy
BTime base accuracy
CTemperature coefficient of the logic
DDecade divider accuracy

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

SelectAnswer
AIt limits the receiver's ability to receive strong signals
BIt decreases receiver third-order intermodulation distortion dynamic range
CIt can cause strong signals on nearby frequencies to interfere with reception of weak signals
DIt reduces receiver sensitivity

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

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
AUse of braided shielding material
BCommon mode currents on the shield and conductors
CTying all ground connections to a common point resulting in differential mode currents in the shield
DLow inductance ground connections at both ends of the shield

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

SelectAnswer
AConductance
BResistance
CCapacitance
DResonance

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

SelectAnswer
A14 degrees with the voltage leading the current
B76 degrees with the voltage lagging the current
C76 degrees with the voltage leading the current
D14 degrees with the voltage lagging the current

22. - E5C04

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

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

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
B0.866
C1.73
D0.5

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

SelectAnswer
AInsulator impurity
BAcceptor impurity
CN-type impurity
DDonor impurity

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

SelectAnswer
AReverse bias controls its forward voltage drop
BA large region of intrinsic material
CExtremely high reverse breakdown voltage
DAbility to dissipate large amounts of power

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

SelectAnswer
A3
B4
C2
D1

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

SelectAnswer
AMagnetic flux would increase with frequency
BHarmonics and distortion could result
CRF susceptance would increase
DTemporary changes of the core permeability could result

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

SelectAnswer
AStripped lead
BSurface mount
CDirect soldering
DVirtual lead mounting

29. - E6F14

Which of the following is true of LCD displays?

SelectAnswer
AThey only display alphanumeric symbols
BThey are hard to view in high ambient light conditions
CThey may be hard view through polarized lenses
DAll of these choices are correct

30. - E7A12

What type of logic defines "0" as a high voltage?

SelectAnswer
AAssertive Logic
BReverse Logic
CPositive Logic
DNegative logic

31. - E7B10

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

SelectAnswer
ALoad resistors
BSelf bias
CFeedback
DFixed bias

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
AHigher efficiency
BGreater transformation range
CGreater harmonic suppression
DLower losses

33. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-3?

SelectAnswer
ATo self-resonate at the hum frequency
BIt is a brute force filter for the output
CTo provide fixed DC bias for Q1
DIt bypasses hum around D1

34. - E7E03

How does an analog phase modulator function?

SelectAnswer
ABy varying the tuning of a microphone preamplifier to produce PM signals
BBy varying the tuning of an amplifier tank circuit to produce PM signals
CBy varying the tuning of an amplifier tank circuit to produce AM signals
DBy varying the tuning of a microphone preamplifier to produce AM signals

35. - E7F17

What do the letters I and Q in I/Q Modulation represent?

SelectAnswer
AInstantaneous and Quenched
BIn-phase and Quadrature
CInactive and Quiescent
DInstantaneous and Quasi-stable

36. - E7G12

What is an integrated circuit operational amplifier?

SelectAnswer
AAn amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
BA digital audio amplifier whose characteristics are determined by components external to the amplifier
CA RF amplifier used in the UHF and microwave regions
DA high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

SelectAnswer
ABias the crystal at a specified current
BProvide the crystal with a specified parallel inductance
CBias the crystal at a specified voltage
DProvide the crystal with a specified parallel capacitance

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

SelectAnswer
AAll of these choices are correct
BRemove harmonics from the output caused by the discrete analog levels generated
CImprove accuracy by removing out of sequence codes from the input
DLower the input bandwidth to increase the effective resolution

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
B2.14
C47
D0.214

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A15.36 kHz
B9.6 kHz
C4.8 kHz
D5.76 kHz

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

SelectAnswer
AStrong ALC action
BHarmonics on higher bands
CRapid signal fading
DHigh reflected power

42. - E9A16

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

SelectAnswer
A300 watts
B317 watts
C2000 watts
D126 watts

43. - E9B10

What is the principle of a Method of Moments analysis?

SelectAnswer
AA wire is modeled as a single sine-wave current generator
BA wire is modeled as a series of segments, each having a uniform value of current
CA wire is modeled as a series of points, each having a distinct location in space
DA wire is modeled as a series of segments, each having a distinct value of voltage across it

44. - E9C08

What is a folded dipole antenna?

SelectAnswer
AA dipole consisting of one wavelength of wire forming a very thin loop
BA dipole one-quarter wavelength long
CA type of ground-plane antenna
DA dipole configured to provide forward gain

45. - E9D03

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

SelectAnswer
AAt a voltage node
BNear the center of the vertical radiator
CAs close to the transmitter as possible
DAs low as possible on the vertical radiator

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

SelectAnswer
AUse the universal stub matching technique
BUse a 50 ohm 1:1 balun between the antenna and feed line
CConnect a series-resonant LC network across the antenna feed terminals
DConnect a parallel-resonant LC network across the antenna feed terminals

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AThe same as the input impedance to the generator
BThe same as the characteristic impedance of the line
CVery high impedance
DVery low impedance

48. - E9G09

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

SelectAnswer
AStanding wave ratio circles
BAntenna-length circles
CRadiation-pattern circles
DCoaxial-length circles

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

SelectAnswer
AOne or more turns of wire wound in the shape of a large open coil
BA vertical antenna coupled to a feed line through an inductive loop of wire
CA small coil of wire tightly wound around a toroidal ferrite core
DA large circularly polarized antenna

50. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

SelectAnswer
APolychlorinated Biphenyls
BPolytetrafluroethylene
CPolyethylene
DPolymorphic silicon

Figure E6-5

Figure E7-1

Figure E7-3