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?

Select	Answer
A	1 kHz above the lower band edge
B	3 kHz above the lower band edge
C	The exact lower band edge
D	300 Hz 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?

Select	Answer
A	The location is near an area of political conflict
B	The location is of environmental importance or significant in American history, architecture, or culture
C	The location is of geographical or horticultural importance
D	The location is in an ITU Zone designated for coordination with one or more foreign governments

3. - E1C01

What is a remotely controlled station?

Select	Answer
A	A station operating under automatic control
B	A station controlled by someone other than the licensee
C	A station controlled indirectly through a control link
D	A station operated away from its regular home location

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	Two-way single channel transmissions of data
B	Two-way radiotelephone transmissions in excess of 1000 feet
C	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
D	One-way transmission of measurements at a distance from the measuring instrument

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	Photocopy all examination documents and forward them to the FCC for processing
B	All these choices are correct
C	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
D	Issue the examinee the new or upgrade license

6. - E1F10

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

Select	Answer
A	1.5 W
B	10 W
C	1 W
D	1.5 kW

7. - E2A13

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

Select	Answer
A	LEO
B	HEO
C	Geostationary
D	Geomagnetic

8. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

Select	Answer
A	By scanning two fields simultaneously
B	By scanning odd numbered lines in one field and even numbered lines in the next
C	By scanning each field from bottom to top
D	By scanning lines from left to right in one field and right to left in the next

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Contacts using tactical call signs
B	Special event contacts between stations in the U.S.
C	Repeater contacts between U.S. club members
D	Contacts between a U.S. station and a non-U.S. station

10. - E2D14

What is one advantage of using JT65 coding?

Select	Answer
A	Easily copied by ear if necessary
B	Uses only a 65 Hz bandwidth
C	Permits fast-scan TV transmissions over narrow bandwidth
D	The ability to decode signals which have a very low signal to noise ratio

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	RTTY
B	PSK31
C	PACTOR
D	MT63

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

Select	Answer
A	Sprites and jets
B	Lightning discharges
C	Warm and cold fronts
D	Gray-line

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Noon
B	Afternoon or early evening
C	Morning
D	Late at night

14. - E3C04

What does the value of Bz (B sub Z) represent?

Select	Answer
A	Direction and strength of the interplanetary magnetic field
B	Duration of long-delayed echoes
C	Critical frequency for vertical transmissions
D	Geomagnetic field stability

15. - E4A02

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

Select	Answer
A	RF amplitude and frequency
B	SWR and frequency
C	SWR and time
D	RF amplitude and time

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S21
B	S22
C	S12
D	S11

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Overload
B	Loss of sensitivity
C	Distortion
D	Excess output level

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A properly terminated circulator at the output of the transmitter
B	A band-pass filter in the feed line between the transmitter and receiver
C	A Class D final amplifier
D	A Class C final amplifier

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	An electrical-sparking signal
B	Harmonics of the AC power line frequency
C	A differential-mode signal at the AC power line frequency
D	A common-mode signal at the frequency of the radio transmitter

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

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	220 seconds
B	440 seconds
C	55 seconds
D	110 seconds

22. - E5C04

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

Select	Answer
A	A negative phase angle
B	A positive phase angle
C	A positive real part
D	A negative real part

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Permittivity
B	Malleability
C	Permeability
D	Inductance

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
B	To provide a voltage reference for the correct amount of reverse-bias gate voltage
C	To protect the substrate from excessive voltages
D	To keep the gate voltage within specifications and prevent the device from overheating

25. - E6B06

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

Select	Answer
A	As a VHF/UHF mixer or detector
B	As a variable capacitance in an automatic frequency control circuit
C	As balanced mixers in FM generation
D	As a constant voltage reference in a power supply

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	The input switching threshold is about two times the power supply voltage
B	Input signals are stronger
C	The input switching threshold is about one-half the power supply voltage
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Thermal impedance
B	Resistance
C	Permeability
D	Reactivity

28. - E6E11

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

Select	Answer
A	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
B	Low leakage doubly insulated package
C	Two chips in each package (Dual In Package)
D	Package mounts in a direct inverted position

29. - E6F13

What is a liquid crystal display (LCD)?

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

30. - E7A12

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

Select	Answer
A	Reverse Logic
B	Positive Logic
C	Negative logic
D	Assertive Logic

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	High power gain
B	Low input impedance
C	Low bandwidth
D	High filament voltage

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Extremely sharp cutoff with one or more notches in the stop band
B	Gradual passband rolloff with extreme stop band ripple
C	Gradual passband rolloff with minimal stop band ripple
D	Extremely flat response over its pass band with gradually rounded stop band corners

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Grounded emitter amplifier
B	Switching voltage regulator
C	Emitter follower
D	Linear voltage regulator

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce AM signals
B	By varying the tuning of an amplifier tank circuit to produce AM signals
C	By varying the tuning of a microphone preamplifier to produce PM signals
D	By varying the tuning of an amplifier tank circuit to produce PM signals

35. - E7F17

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

Select	Answer
A	In-phase and Quadrature
B	Instantaneous and Quasi-stable
C	Instantaneous and Quenched
D	Inactive and Quiescent

36. - E7G12

What is an integrated circuit operational amplifier?

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

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Photovoltaic conversion, optical coupling
B	Wide-band AF and RF power amplification
C	Frequency synthesis, FM demodulation
D	Comparison of two digital input signals, digital pulse counter

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Vector analysis
B	Fourier analysis
C	Numerical analysis
D	Differential analysis

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A frequency modulation technique which uses non-harmonically related frequencies
B	A digital mode for narrow band, slow speed transmissions
C	A bandwidth compression technique using Fourier transforms
D	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The rate at which the waveform of a transmitted signal changes to convey information
B	The duration of each bit in a message sent over the air
C	The number of characters carried per second by the station-to-station link
D	The number of control characters in a message packet

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Ground loops
B	Excessive numbers of retries
C	Bit errors in the modem
D	Excessive transmit audio levels

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Install a good radial system
B	Shorten the radiating element
C	Reduce the diameter of the radiating element
D	Isolate the coax shield from ground

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

Select	Answer
A	30 degrees
B	50 degrees
C	75 degrees
D	25 degrees

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
B	An omni-directional antenna commonly used for satellite communications
C	An end fed dipole antenna
D	A dipole constructed from zip cord

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance increases and the capacitive reactance decreases
B	The radiation resistance increases and the capacitive reactance increases
C	The radiation resistance decreases and the capacitive reactance increases
D	The radiation resistance decreases and the capacitive reactance decreases

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To provide a rejection notch that prevents the radiation of harmonics
B	To cancel the inductive reactance of the matching network
C	To provide DC isolation between the feed line and the antenna
D	To transform the antenna impedance to a higher value

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

48. - E9G09

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

Select	Answer
A	Radiation-pattern circles
B	Coaxial-length circles
C	Standing wave ratio circles
D	Antenna-length circles

49. - E9H04

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

Select	Answer
A	It allows stations to communicate without giving away their position
B	It is electro statically balanced against ground, giving better nulls
C	It automatically cancels ignition noise in mobile installations
D	It eliminates tracking errors caused by strong out-of-band signals

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Make sure signals from your station are less than the controlled MPE limits
B	Make sure signals from your station are less than the uncontrolled MPE limits
C	You need only evaluate exposure levels on your own property
D	Advise your neighbors of the results of your tests

Figure E7-3

Figure E9-1