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

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1. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

Select	Answer
A	Only a person with an FCC Marine Radio
B	Only a person named in an amateur station license grant
C	Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
D	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 43 dB below
B	At least 63 dB below
C	At least 53 dB below
D	At least 73 dB below

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	3 minutes
B	10 minutes
C	5 minutes
D	30 seconds

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	6 meters, 2 meters, and 1.25 meters
B	6 meters and 2 meters
C	2 meters and 1.25 meters
D	2 meters

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	4
B	5
C	3
D	2

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Technician, General, Advanced or Amateur Extra Class operators
B	Only Amateur Extra Class operators
C	Only General, Advanced or Amateur Extra Class operators
D	Any licensed amateur operator

7. - E2A04

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

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

8. - E2B15

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

Select	Answer
A	A two-tone signal
B	Elapsed time
C	Specific tone frequencies
D	Specific tone amplitudes

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	2 m
B	33 cm
C	6 m
D	30 m

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
C	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
D	All of these choices are correct

11. - E2E05

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

Select	Answer
A	Winlink
B	MFSK
C	PSK31
D	RTTY

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves with a rotating electric field
B	Waves produced by a loop antenna
C	Waves with an electric field bent into a circular shape
D	Waves that circle the Earth

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	30 meters to 10 meters
B	160 meters to 10 meters
C	160 meters to 40 meters
D	6 meters to 2 meters

14. - E3C13

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

Select	Answer
A	Elliptical
B	Vertical
C	Circular
D	Horizontal

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
B	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
C	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
D	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

Select	Answer
A	The transmitter is not properly neutralized
B	There is possibly a short to ground in the feed line
C	There is an impedance mismatch between the antenna and feed line
D	There is more power going into the antenna

17. - E4C13

How does a narrow-band roofing filter affect receiver performance?

Select	Answer
A	It improves intelligibility by using low Q circuitry to reduce ringing
B	All of these choices are correct
C	It improves dynamic range by attenuating strong signals near the receive frequency
D	It improves sensitivity by reducing front end noise

18. - E4D02

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

Select	Answer
A	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
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	Oscillator instability and severe audio distortion of all but the strongest received signals

19. - E4E15

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

Select	Answer
A	Low inductance ground connections at both ends of the shield
B	Common mode currents on the shield and conductors
C	Tying all ground connections to a common point resulting in differential mode currents in the shield
D	Use of braided shielding material

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	3.56 MHz
B	44.72 MHz
C	22.36 MHz
D	1.78 MHz

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?

Select	Answer
A	14 degrees with the voltage leading the current
B	76 degrees with the voltage leading the current
C	76 degrees with the voltage lagging the current
D	14 degrees with the voltage lagging the current

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The coordinate values along the horizontal and vertical axes
B	The tangent and cotangent values
C	The magnitude and phase of the point
D	The sine and cosine values

23. - E5D08

What type of energy is stored in an electromagnetic or electrostatic field?

Select	Answer
A	Potential energy
B	Thermodynamic energy
C	Kinetic energy
D	Electromechanical energy

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	P-type
B	N-type
C	Bipolar
D	Insulated gate

25. - E6B04

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

Select	Answer
A	Tunnel diode
B	Silicon-controlled rectifier
C	Varactor diode
D	Zener 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	A PGA contains its own internal power supply
C	All of these choices are correct
D	Complex logic functions can be created in a single integrated circuit

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores exhibit greater hysteresis
B	Toroidal cores confine most of the magnetic field within the core material
C	Toroidal cores make it easier to couple the magnetic energy into other components
D	Toroidal cores have lower Q characteristics

28. - E6E06

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

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

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	A heavy metal
B	A crystalline semiconductor
C	A liquid semiconductor
D	An ordinary metal

30. - E7A10

What is a truth table?

Select	Answer
A	A table of logic symbols that indicate the logic states of an op-amp
B	A table of logic symbols that indicate the high logic states of an op-amp
C	A diagram showing logic states when the digital device output is true
D	A list of inputs and corresponding outputs for a digital device

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

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

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D05

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

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

34. - E7E10

How does a diode detector function?

Select	Answer
A	By rectification and filtering of RF signals
B	By sensing the change of reactance in the diode with respect to frequency
C	By mixing signals with noise in the transition region of the diode
D	By breakdown of the Zener voltage

35. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A crystal-lattice filter
B	An adaptive filter
C	A phase-inverting filter
D	A Hilbert-transform filter

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	0.07
B	7
C	14
D	28

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A hybrid synthesizer
B	A direct digital synthesizer
C	A phase locked loop synthesizer
D	A diode-switching matrix synthesizer

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	1 to 1
B	2.5 to 1
C	100 to 1
D	25 to 1

39. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	0.6
B	60
C	0.167
D	1.67

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Use of trapezoidal data pulses
B	Use of sinusoidal data pulses
C	Reed-Solomon character encoding
D	Zero-sum character encoding

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	The receiver is always equipped with a digital blanker
B	Signals not using the spread spectrum algorithm are suppressed in the receiver
C	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A05

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

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

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a single sine-wave current generator
B	A wire is modeled as a series of points, each having a distinct location in space
C	A wire is modeled as a series of segments, each having a distinct value of voltage across it
D	A wire is modeled as a series of segments, each having a uniform value of current

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

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

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The frequency response is widened over the whole frequency band
B	The SWR is reduced
C	The front-to-back ratio decreases
D	The front-to-back ratio increases

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	A dielectric constant greater than 1
B	An SWR less than 1:1
C	An SWR greater than 1:1
D	A reflection coefficient greater than 1

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

48. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Satellite azimuth and elevation bearings
B	Trigonometric functions
C	Impedance and SWR values in transmission lines
D	Beam headings and radiation patterns

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	A very sharp peak
B	High-radiation angle
C	Broad band response
D	A very sharp single null

50. - E0A08

What does SAR measure?

Select	Answer
A	The rate at which RF energy is absorbed by the body
B	Synthetic Aperture Ratio of the human body
C	The rate of RF energy reflected from stationary terrain
D	Signal Amplification Rating

Figure E7-4