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?

Select	Answer
A	Yes, the DX station initiated the contact
B	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz
C	No, one of the sidebands of the CW signal will be out of the band
D	Yes, the displayed frequency is within the 80 meter CW band segment

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	3 miles
C	30 miles
D	1 mile

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	You must append "/CEPT" to your call sign
B	You must bring a copy of FCC Public Notice DA 11-221
C	You must identify in the official language of the country in which you are operating
D	The U.S. embassy must approve of your operation

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Any amateur station, subject to the privileges of the class of operator license held by the control operator
B	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
C	Only those of General, Advanced or Amateur Extra Class operators
D	Only those of Amateur Extra Class operators

5. - E1E08

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

Select	Answer
A	Relatives of the VE as listed in the FCC rules
B	All of these choices are correct
C	Employees of the VE
D	Friends of the VE

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?

Select	Answer
A	440 MHz - 450 MHz
B	53 MHz - 54 MHz
C	420 MHz - 430 MHz
D	222 MHz - 223 MHz

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The polarization of uplink and downlink signals
B	Power limits for uplink and downlink transmissions
C	The location of the ground control station
D	The uplink and downlink frequency ranges

8. - E2B07

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

Select	Answer
A	Hue
B	Spectral Intensity
C	Luminance
D	Chroma

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A method of exchanging information during a contest QSO
B	A standard for submission of electronic contest logs
C	The most common set of contest rules
D	The rules of order for meetings between contest sponsors

10. - E2D11

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

Select	Answer
A	Polar coordinates
B	Radio direction finding spectrum analysis
C	Time and frequency
D	Latitude and longitude

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK applies the data signal to the transmitter VFO
B	Direct FSK uses a DC-coupled data connection
C	Audio FSK can be performed anywhere in the transmit chain
D	Audio FSK has a superior frequency response

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	10 miles to 50 miles
B	2500 miles
C	100 miles to 300 miles
D	1200 miles

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
B	Propagation between any two points located on the magnetic equator
C	Propagation between two continents by way of ducts along the magnetic equator
D	Propagation between two stations at the same latitude

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Decreasing disruption of the geomagnetic field
B	An increase in the critical frequency
C	Higher levels of solar UV radiation
D	Increasing disruption of the geomagnetic field

15. - E4A06

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

Select	Answer
A	Calibration of the vertical scale is no longer valid
B	False signals are displayed
C	All signals will have a DC offset
D	False triggering occurs

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S21
B	S11
C	S12
D	S22

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The minimum discernible signal
B	The maximum detectable spectrum
C	The meter display sensitivity
D	The multiplex distortion stability

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	The off-frequency unwanted signal is heard in addition to the desired signal
B	A reduction in apparent signal strength
C	The desired signal can no longer be heard
D	A large increase in background noise

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By observing the AC power line waveform with an oscilloscope
B	By checking the power line voltage with a time domain reflectometer
C	By observing the AC power line voltage with a spectrum analyzer
D	By turning off the AC power line main circuit breaker and listening on a battery operated radio

20. - E5A04

What is the magnitude of the impedance of a circuit with a resistor, an inductor and a capacitor all in parallel, at resonance?

Select	Answer
A	Approximately equal to circuit resistance
B	Approximately equal to capacitive reactance
C	Low, as compared to the circuit resistance
D	Approximately equal to inductive reactance

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	B
B	X
C	Y
D	G

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 7
B	Point 3
C	Point 8
D	Point 1

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Permeability
B	Inductance
C	Permittivity
D	Malleability

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free neutrons
B	Holes
C	Free protons
D	Free electrons

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Forward bias
B	Inductive bias
C	Zero bias
D	Reverse bias

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	Complex logic functions can be created in a single integrated circuit
B	Many similar gates are less expensive than a mixture of gate types
C	A PGA contains its own internal power supply
D	All of these choices are correct

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
C	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
D	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Nearly infinite gain, very high input impedance, and very low output impedance
B	The ability to retrieve information from a single signal even in the presence of other strong signals
C	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
D	Plate current that is controlled by a control grid

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A display that uses a glowing liquid to remain brightly lit in dim light
B	A frequency-determining unit for a transmitter or receiver
C	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency
D	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic "1" at its output only if all inputs are logic "1"
B	It produces logic "1" at its output if any single input is logic "1"
C	It produces logic "0" at its output if any single input is logic "1"
D	It produces logic "0" at its output only if all inputs are logic "0"

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	Use a resistor in series with the emitter
B	Neutralization
C	All of these choices are correct
D	Select transistors with high beta

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a high-pass filter
B	It is a low-pass filter
C	It is a band-pass filter
D	It is a notch filter

33. - E7D07

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

Select	Answer
A	It is a brute force filter for the output
B	It bypasses hum around D1
C	To self-resonate at the hum frequency
D	To provide fixed DC bias for Q1

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	A beat frequency is generated
B	Mixer blanking occurs
C	Automatic limiting occurs
D	Spurious mixer products are generated

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Sample clock phase noise
B	Data storage transfer rate
C	Missing codes and jitter
D	Reference voltage level and sample width in bits

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A digital audio amplifier whose characteristics are determined by components external to the amplifier
B	A RF amplifier used in the UHF and microwave regions
C	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
D	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a quartz crystal
B	Through a tapped coil
C	Through a neutralizing capacitor
D	Through link coupling

38. - E8A08

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

Select	Answer
A	All of these choices are correct
B	Immunity to out of sequence coding reduces spurious responses
C	Very low power consumption decreases frequency drift
D	Very high speed allows digitizing high frequencies

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It does not depend on the RF carrier frequency
B	It increases as the RF carrier frequency increases
C	It varies with the square root of the RF carrier frequency
D	It decreases as the RF carrier frequency increases

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is only used for RTTY
B	They are the same
C	Symbol rate is only used for packet-based modes
D	Baud is twice the symbol rate

41. - E8D10

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

Select	Answer
A	Baudot 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
B	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
C	Baudot 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
D	Baudot 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

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Radiation resistance plus transmission resistance
B	Radiation resistance plus space impedance
C	Radiation resistance plus ohmic resistance
D	Transmission-line resistance plus radiation resistance

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region where the shape of the antenna pattern is independent of distance
B	The region where radiated field strengths are obstructed by objects of reflection
C	The region of the ionosphere where radiated power is not refracted
D	The region where radiated power dissipates over a specified time period

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?

Select	Answer
A	A figure-8 broadside to the axis of the array
B	A figure-8 end-fire along the axis of the array
C	Omni-directional
D	Cardioid

45. - E9D03

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

Select	Answer
A	As close to the transmitter as possible
B	Near the center of the vertical radiator
C	At a voltage node
D	As low as possible on the vertical radiator

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	Pi-network
B	Pi-L-network
C	A series capacitor
D	A shunt inductor

47. - E9F14

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

Select	Answer
A	The same as the characteristic impedance of the line
B	The same as the output impedance of the generator
C	Very high impedance
D	Very low impedance

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning reactance values with regard to the resistance axis
B	Reassigning impedance values with regard to the prime center
C	Reassigning prime center with regard to the reactance axis
D	Reassigning resistance values with regard to the reactance axis

49. - E9H05

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

Select	Answer
A	It is practical for use only on VHF bands
B	It is non-rotatable
C	It has a bidirectional pattern
D	It receives equally well in all directions

50. - E0A05

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

Select	Answer
A	Microwaves are ionizing radiation
B	The extremely high frequency energy can damage the joints of antenna structures
C	The high gain antennas commonly used can result in high exposure levels
D	Microwaves often travel long distances by ionospheric reflection

Figure E5-2

Figure E7-3