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

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
B	No special rules apply if your antenna structure will be less than 300 feet in height
C	You must obtain a construction permit from the airport zoning authority
D	You must file an Environmental Impact Statement with the EPA before construction begins

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	ITU reciprocal license
B	IARP agreement
C	CEPT agreement
D	All of these choices are correct

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	All HF bands
B	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions
B	They must collect and submit the documents to the coordinating VEC for grading
C	They must collect and send the documents to the FCC according to instructions
D	They must collect and send the documents to the NCVEC for grading

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 420 MHz
B	Only on amateur frequencies above 144 MHz
C	Only on amateur frequencies above 50 MHz
D	Only on amateur frequencies above 222 MHz

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From south to north
B	From west to east
C	From north to south
D	From east to west

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

Select	Answer
A	The vestigial sideband contains chroma information
B	The vestigial sideband carries the audio information
C	Vestigial sideband provides high frequency emphasis to sharpen the picture
D	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send your full call sign and grid square
B	Send the call sign of the DX station three times, the words "this is", then your call sign three times
C	Send only the last two letters of your call sign until you make contact
D	Send your full call sign once or twice

10. - E2D09

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

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

11. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	PACTOR
B	AMTOR
C	RTTY
D	Hellschreiber

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of two magnetic fields at right angles to each other
B	A wave of alternating current, in the core of an electromagnet
C	A wave consisting of two electric fields at parallel right angles to each other
D	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other

13. - E3B10

What is the cause of gray-line propagation?

Select	Answer
A	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves
B	At twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high
C	In darkness, solar absorption drops greatly while atmospheric ionization remains steady
D	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately twice the distance
B	By approximately 15 percent of the distance
C	By approximately 50 percent of the distance
D	By approximately four times the distance

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A spectrum analyzer
B	A wattmeter
C	A logic analyzer
D	A time-domain reflectometer

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 ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
C	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
D	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

17. - E4C13

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

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

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
B	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
C	When the signals from the transmitters are reflected in phase from airplanes passing overhead
D	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A clicking noise at intervals of a few seconds
B	The appearance of unstable modulated or unmodulated signals at specific frequencies
C	A whining type noise that continually pulses off and on
D	A loud AC hum in the audio output of your station receiver

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance
B	It is at a maximum
C	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
D	It is at a minimum

21. - E5B09

What is the relationship between the current through a capacitor and the voltage across a capacitor?

Select	Answer
A	Voltage leads current by 90 degrees
B	Voltage and current are in phase
C	Voltage and current are 180 degrees out of phase
D	Current leads voltage by 90 degrees

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

Select	Answer
A	Point 2
B	Point 4
C	Point 5
D	Point 6

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	1.73
B	0.866
C	0.5
D	1.414

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	An FET has low input impedance; a bipolar transistor has high input impedance
B	They are both low impedance
C	They are both high impedance
D	An FET has high input impedance; a bipolar transistor has low input impedance

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	A sub-harmonic pump signal
B	Reverse voltage larger than the RF signal
C	Forward DC bias current
D	Capacitance of an RF coupling capacitor

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	Its simplicity results in much less expensive devices than standard CMOS
B	All of these choices are correct
C	It is totally immune to electrostatic damage
D	It has the high input impedance of CMOS and the low output impedance of bipolar transistors

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

Select	Answer
A	From a few kHz to no more than 30 MHz
B	From about 100 kHz to at least 1000 GHz
C	From approximately 10 Hz to no more than 3000 kHz
D	From less than 20 Hz to approximately 300 MHz

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	The ability to retrieve information from a single signal even in the presence of other strong signals
C	Nearly infinite gain, very high input impedance, and very low output impedance
D	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators eliminate the effects of reflected light in the control circuit
B	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
C	Optoisolators provide a low impedance link between a control circuit and a power circuit
D	Optoisolators provide impedance matching between the control circuit and power circuit

30. - E7A12

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

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

31. - E7B02

What is a Class D amplifier?

Select	Answer
A	A type of amplifier that uses switching technology to achieve high efficiency
B	A frequency doubling amplifier
C	A low power amplifier that uses a differential amplifier for improved linearity
D	An amplifier that uses drift-mode FETs for high efficiency

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	It gives a ramp voltage at its output
B	It is generally less efficient than a linear regulator
C	The controlled device's duty cycle is changed to produce a constant average output voltage
D	The resistance of a control element is varied in direct proportion to the line voltage or load current

34. - E7E10

How does a diode detector function?

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

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	A notch filter
B	An elliptical filter
C	An adaptive filter
D	A Hilbert-transform filter

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	94
B	47
C	0.21
D	24

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Taft, Pierce and negative feedback
B	Pierce, Fenner and Beane
C	Taft, Hartley and Pierce
D	Colpitts, Hartley and Pierce

38. - E8A10

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

Select	Answer
A	Improve accuracy by removing out of sequence codes from the input
B	Remove harmonics from the output caused by the discrete analog levels generated
C	Lower the input bandwidth to increase the effective resolution
D	All of these choices are correct

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Modulation index
B	Percentage of modulation
C	FM compressibility
D	Quieting index

40. - E8C11

What is the relationship between symbol rate and baud?

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

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	Limits data speed
B	The generation of key clicks
C	More difficult to copy
D	The generation of RF harmonics

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(effective radiated power / transmitter output) x 100 percent
B	(total resistance / radiation resistance) x 100 per cent
C	(radiation resistance / total resistance) x 100 per cent
D	(radiation resistance / transmission resistance) x 100 per cent

43. - E9B12

What is the far field of an antenna?

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

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It changes the impedance angle of the matching network
B	It causes increased SWR
C	It reduces low-angle radiation
D	It reduces losses in the radiating portion of the antenna

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain increases by 6 dB
B	Gain increases by 3 dB
C	Gain does not change
D	Gain is multiplied by 0.707

46. - E9E13

What is a use for a Wilkinson divider?

Select	Answer
A	It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedance
B	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
C	It is used to feed high-impedance antennas from a low-impedance source
D	It is used to feed low-impedance loads from a high-impedance source

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Lower velocity factor
B	Higher SWR
C	Lower loss
D	Smaller reflection coefficient

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Points with constant reactance
B	Points with constant resistance
C	SWR
D	Frequency

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It should be configured as a four-sided loop
B	It must be mounted more than 1 wavelength above ground
C	Its overall length must not exceed 1/4 wavelength
D	It should be one or more wavelengths long

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	Ground reflections and scattering make the field impedance vary with location
B	The body reacts to electromagnetic radiation from both the E and H fields
C	E field and H field radiation intensity peaks can occur at different locations
D	All of these choices are correct

Figure E5-2

Figure E7-4