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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

SelectAnswer
ANo, U.S. stations are not permitted to use phone emissions above 14.340 MHz
BYes, because the displayed frequency is within the 20 meter band
CYes, because you were not the station calling CQ
DNo, the sideband will extend beyond the band edge

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

SelectAnswer
AMilitary Auxiliary Radio System (MARS) channels
BSpecific segments in the amateur service MF, HF, VHF and UHF bands
CSpecific local government channels
DAll amateur service frequencies authorized to the control operator

3. - E1C05

When may an automatically controlled station originate third party communications?

SelectAnswer
AOnly when transmitting RTTY or data emissions
BWhen approved by the National Telecommunication and Information Administration
CNever
DWhen agreed upon by the sending or receiving station

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
COnly those of General, Advanced or Amateur Extra Class operators
DAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

SelectAnswer
AIn the appropriate FCC Report and Order
BIn FCC Part 97
CIn a question pool maintained by the FCC
DIn a question pool maintained by all the VECs

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

SelectAnswer
A1 W
B1.5 W
C1.5 kW
D10 W

7. - E2A13

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

SelectAnswer
ALEO
BHEO
CGeomagnetic
DGeostationary

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

SelectAnswer
A10 KHz
B3 KHz
C15 KHz
D20 KHz

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

SelectAnswer
AStore and forward on the 440 MHz band
BFrequency division multiplex in the 24 GHz band
CMultiple Frequency Shift Keying in the 10 GHz band
DSpread spectrum in the 2.4 GHz band

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

SelectAnswer
ALatitude and longitude
BPolar coordinates
CRadio direction finding spectrum analysis
DTime and frequency

11. - E2E11

What is the difference between direct FSK and audio FSK?

SelectAnswer
AAudio FSK can be performed anywhere in the transmit chain
BAudio FSK has a superior frequency response
CDirect FSK uses a DC-coupled data connection
DDirect FSK applies the data signal to the transmitter VFO

12. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

SelectAnswer
A5000 miles, if the Moon is at perigee
B2000 miles, if the Moon is at apogee
C12,000 miles, if the Moon is visible by both stations
D500 miles, if the Moon is at perigee

13. - E3B11

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

SelectAnswer
AAny time
BAround sunset
CAround sunrise
DEarly evening

14. - E3C10

What does the 304A solar parameter measure?

SelectAnswer
AThe ratio of X-Ray flux to radio flux, correlated to sunspot number
BUV emissions at 304 angstroms, correlated to solar flux index
CThe solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
DThe solar emission at 304 GHz, correlated to X-Ray flare levels

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

SelectAnswer
AInput impedance
BSampling rate
CInput capacitance
DSample resolution

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

SelectAnswer
AShort circuit, open circuit, and resonant circuit
B50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
CShort circuit, open circuit, and 50 ohms
D50 ohms, 75 ohms, and 90 ohms

17. - E4C04

How is the noise figure of a receiver defined?

SelectAnswer
AThe ratio in dB of the noise generated by the receiver to the theoretical minimum noise
BThe ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network
CThe ratio of atmospheric noise to phase noise
DThe ratio of thermal noise to atmospheric noise

18. - E4D09

What is the purpose of the preselector in a communications receiver?

SelectAnswer
ATo store often-used frequencies
BTo provide a range of AGC time constants
CTo allow selection of the optimum RF amplifier device
DTo increase rejection of unwanted signals

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

SelectAnswer
AReceived CW signals will appear to be modulated at the DSP clock frequency
BA DSP filter can remove the desired signal at the same time as it removes interfering signals
CRinging in the DSP filter will completely remove the spaces between the CW characters
DAny nearby signal passing through the DSP system will overwhelm the desired signal

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

SelectAnswer
A31.4 kHz
B15.7 kHz
C436.6 kHz
D218.3 kHz

21. - E5B03

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

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

22. - E5C16

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

SelectAnswer
APoint 7
BPoint 3
CPoint 8
DPoint 1

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

SelectAnswer
AIn a direction opposite to the current
BIn the same direction as the current
CIn all directions; omni-directional
DIn a direction determined by the left-hand rule

24. - E6A05

What is the alpha of a bipolar junction transistor?

SelectAnswer
AThe change of collector current with respect to gate current
BThe change of collector current with respect to base current
CThe change of base current with respect to collector current
DThe change of collector current with respect to emitter current

25. - E6B06

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

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

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
ALower power consumption
BLower distortion
CImmune to damage from static discharge
DDifferential output capability

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

SelectAnswer
A141 turns
B13 turns
C79 turns
D35 turns

28. - E6E02

Which of the following device packages is a through-hole type?

SelectAnswer
APLCC
BSOT
CDIP
DBall grid array

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

SelectAnswer
AIt increases
BIt decreases
CIt becomes unstable
DIt stays the same

30. - E7A01

Which is a bi-stable circuit?

SelectAnswer
AA flip-flop
BAn "AND" gate
CA clock
DAn "OR" gate

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

SelectAnswer
AA matched load resistor to prevent damage by switching transients
BA low-pass filter to remove switching signal components
CA high-pass filter to compensate for low gain at low frequencies
DA temperature compensating load resistor to improve linearity

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

SelectAnswer
AA passive op-amp filter
BA Chebyshev filter
CA Butterworth filter
DAn active LC filter

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

SelectAnswer
AIt gives a ramp voltage at its output
BThe resistance of a control element is varied in direct proportion to the line voltage or load current
CIt is generally less efficient than a linear regulator
DThe controlled device's duty cycle is changed to produce a constant average output voltage

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
ATo reduce impulse noise reception
BFor compatibility with transmitters using phase modulation
CFor higher efficiency
DTo remove third-order distortion products

35. - E7F01

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

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

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

SelectAnswer
AThrough link coupling
BThrough a capacitive divider
CThrough a tapped coil
DThrough a neutralizing capacitor

38. - E8A10

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

SelectAnswer
ALower the input bandwidth to increase the effective resolution
BImprove accuracy by removing out of sequence codes from the input
CRemove harmonics from the output caused by the discrete analog levels generated
DAll of these choices are correct

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AExtremely low-power contacts
BEME
COFDM signals are not allowed on amateur bands
DHigh speed digital modes

40. - E8C08

How does ARQ accomplish error correction?

SelectAnswer
ASpecial binary codes provide automatic correction
BSpecial polynomial codes provide automatic correction
CIf errors are detected, redundant data is substituted
DIf errors are detected, a retransmission is requested

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
APhase compandored spread spectrum
BDirect sequence
CFrequency hopping
DBinary phase-shift keying

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

SelectAnswer
A8.15 dB
B3.85 dB
C6.0 dB
D2.79 dB

43. - E9B05

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

SelectAnswer
AElevation
BPolarization
CAzimuth
DRadiation resistance

44. - E9C09

What is a G5RV antenna?

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

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

SelectAnswer
AStack two Yagis fed in phase to form an array with the respective elements in parallel planes
BArrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
CArrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
DStack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes

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

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

SelectAnswer
AElectrical signals move more slowly in a coaxial cable than in air
BSkin effect is less pronounced in the coaxial cable
CThe surge impedance is higher in a parallel feed line
DThe characteristic impedance is higher in a parallel feed line

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

SelectAnswer
AIn fractions of transmission line electrical wavelength
BIn fractions of antenna electrical wavelength
CIn fractions of transmission line electrical frequency
DIn fractions of antenna electrical frequency

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

SelectAnswer
AIt has a bidirectional pattern
BIt is practical for use only on VHF bands
CIt receives equally well in all directions
DIt is non-rotatable

50. - E0A08

What does SAR measure?

SelectAnswer
AThe rate at which RF energy is absorbed by the body
BSignal Amplification Rating
CSynthetic Aperture Ratio of the human body
DThe rate of RF energy reflected from stationary terrain

Figure E5-2

Figure E9-2