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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	1 kHz below the upper band edge
B	The exact upper band edge
C	3 kHz below the upper band edge
D	300 Hz below the upper band edge

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	1.0
B	3.0
C	0.5
D	2.0

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	Business-related messages for non-profit organizations
C	Messages intended for connection to users of the maritime satellite service
D	All of these choices are correct

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	All of these choices are correct
B	Any amateur station designated by NASA
C	Any amateur station so designated by the ITU
D	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator

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	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
C	All these choices are correct
D	Issue the examinee the new or upgrade license

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must exhibit a gain of 0 dB or less over its full output range
B	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
C	It must produce full legal output when driven by not more than 5 watts of mean RF input power
D	It must be capable of external RF switching between its input and output networks

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The satellite's orientation with respect to the Earth
B	The type of signals that can be relayed through the satellite
C	The satellite's uplink and downlink frequency bands
D	Whether the satellite is in a polar or equatorial orbit

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

Select	Answer
A	Frequency-modulated sub-carrier
B	All of these choices are correct
C	A separate VHF or UHF audio link
D	Frequency modulation of the video carrier

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
B	Operators are permitted to make contacts even if they do not submit a log
C	Interference to other amateurs is unavoidable and therefore acceptable
D	Every contest requires a signal report in the exchange

10. - E2D09

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

Select	Answer
A	300 baud packet
B	AMTOR
C	170 Hz shift, 45 baud RTTY
D	PSK31

11. - E2E11

What is the difference between direct FSK and audio FSK?

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

12. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Urban areas
B	Bodies of water
C	Forests
D	Mountain ranges

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Successive ionospheric reflections without an intermediate reflection from the ground
B	Propagation across the geomagnetic equator
C	Signals reflected back toward the transmitting station
D	Propagation away from the great circle bearing between stations

14. - E3C13

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

Select	Answer
A	Horizontal
B	Circular
C	Vertical
D	Elliptical

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	Never use a DC-coupled probe to measure an AC circuit
B	All of these choices are correct
C	Never use a high impedance probe to measure a low impedance circuit
D	Keep the signal ground connection of the probe as short as possible

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
B	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
C	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
D	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed

17. - E4C01

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

Select	Answer
A	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
B	It limits the receiver's ability to receive strong signals
C	It decreases receiver third-order intermodulation distortion dynamic range
D	It reduces receiver sensitivity

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Oscillator instability and severe audio distortion of all but the strongest received signals
B	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
C	Cross-modulation of the desired signal and desensitization from strong adjacent signals
D	Cross-modulation of the desired signal and insufficient audio power to operate the speaker

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Differential-mode current
B	Return current
C	Reactive current only
D	Common-mode current

20. - E5A15

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

Select	Answer
A	Lower losses
B	Lower reactance
C	Higher self-resonant frequency
D	Lower self-resonant frequency

21. - E5B03

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

Select	Answer
A	The sign is reversed
B	The susceptance phase angle is the inverse of the reactance phase angle
C	It is shifted by 90 degrees
D	It is unchanged

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Venn diagram
B	Phasor diagram
C	Near field diagram
D	Far field diagram

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as heat in the circuit
B	It is dissipated in the formation of inductive and capacitive fields
C	It is dissipated as kinetic energy in the circuit
D	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated

24. - E6A16

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

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

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Varactor diode
B	Silicon-controlled rectifier
C	Zener diode
D	Tunnel diode

26. - E6C14

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

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

27. - E6D08

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

Select	Answer
A	Powdered-iron cores generally have greater initial permeability
B	Powdered-iron cores generally maintain their characteristics at higher currents
C	Powdered-iron cores use smaller diameter wire for the same inductance
D	Powdered-iron cores generally require fewer turns to produce a given inductance

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It samples an analog signal and passes it in stages from the input to the output
B	Its phase shift changes rapidly with frequency
C	It is used in a battery charger circuit
D	It is a CMOS analog-to-digital converter

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Electrons
B	Photons
C	Holes
D	Protons

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It maintains a constant output voltage, regardless of variations in the input voltage
B	It produces a continuous square wave oscillating between 1 and 0
C	It stores one bit of data in either a 0 or 1 state
D	It switches momentarily to the opposite binary state and then returns to its original state after a set time

31. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	At a point where the load line intersects the zero bias current curve
B	At a point where the bias resistor equals the load resistor
C	Approximately half-way between saturation and cutoff
D	Where the load line intersects the voltage axis

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The DC voltage applied to the quartz crystal
B	The amplitude of the signals passing through the filter
C	The relative frequencies of the individual crystals
D	The gain of the RF stage preceding the filter

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

Select	Answer
A	A shunt regulator
B	A shunt current source
C	A series regulator
D	A constant current source

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	The two input frequencies along with their sum and difference frequencies
B	1.414 and 0.707 times the input frequency
C	The sum, difference and square root of the input frequencies
D	Two and four times the original frequency

35. - E7F01

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

Select	Answer
A	A switching mixer is used to generate I and Q signals directly from the RF input
B	Software is converted from source code to object code during operation of the receiver
C	Incoming RF is converted to a control voltage for a voltage controlled oscillator
D	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	-2.3 volts
B	2.3 volts
C	-0.23 volts
D	0.23 volts

37. - E7H15

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

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

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	Differential analysis
C	Fourier analysis
D	Numerical analysis

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	6000
B	2000
C	3
D	1/3

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By the receiving station repeating each block of three data characters
B	By transmitting extra data that may be used to detect and correct transmission errors
C	By varying the frequency shift of the transmitted signal according to a predefined algorithm
D	By transmitting a special algorithm to the receiving station along with the data characters

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

Select	Answer
A	+15 dB
B	-20 dB
C	+10 dB
D	-30 dB

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The combined losses of the antenna elements and feed line
B	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
C	The specific impedance of the antenna
D	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	14 dB
B	24 dB
C	36 dB
D	18 dB

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	450 ohms
B	50 ohms
C	300 ohms
D	72 ohms

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Improved radiation efficiency
B	Lower Q
C	Higher losses
D	Greater structural strength

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Dielectric constant
B	Velocity factor
C	Characteristic impedance
D	Reflection coefficient

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

48. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Resistance circles and reactance arcs
B	Voltage circles and current arcs
C	Resistance lines and reactance chords
D	Voltage lines and current chords

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It provides diversity reception that cancels multipath signals
B	It allows DF antennas to receive signals at different vertical angles
C	It increases the sensitivity of a DF antenna array
D	It modifies the pattern of a DF antenna array to provide a null in one direction

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Each transmitter operating with a duty-cycle greater than 50 percent
B	Only commercial transmitters
C	Only the most powerful transmitter
D	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations

Figure E7-4

Figure E9-1