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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operators of all the stations in the system not authenticating the source from which they accept communications
B	The control operators of all the stations in the system
C	The control operator of the originating station
D	The control operator of the packet bulletin board station

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 63 dB below
B	At least 73 dB below
C	At least 53 dB below
D	At least 43 dB below

3. - E1C07

What is meant by local control?

Select	Answer
A	Automatically manipulating local station controls
B	Direct manipulation of the transmitter by a control operator
C	Controlling a station through a local auxiliary link
D	Controlling a repeater using a portable handheld transceiver

4. - E1D01

What is the definition of the term telemetry?

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

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	The person who has entered into an agreement with the FCC to be the VE session manager
B	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
C	A person who has volunteered to administer amateur operator license examinations
D	A person who has volunteered to prepare amateur operator license examinations

6. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When transmitting international third-party communications
B	When the control operator is employed by the FCC or another government agency
C	When the total money involved does not exceed $25
D	When neither the amateur nor his or her employer has a pecuniary interest in the communications

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By subtracting the mean anomaly from the orbital inclination
B	By calculations using the Keplerian elements for the specified satellite
C	By means of the Doppler data for the specified satellite
D	By adding the mean anomaly to the orbital inclination

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	30
B	60
C	525
D	1080

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 the call sign of the DX station three times, the words "this is", then your call sign three times
B	Send your full call sign and grid square
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. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	All of these choices are correct
B	It controls the receiver to track Doppler shift
C	It can decode signals many dB below the noise floor using FEC
D	It supplies signals to guide the antenna to track the Moon

11. - E2E05

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

Select	Answer
A	PSK31
B	RTTY
C	Winlink
D	MFSK

12. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

Select	Answer
A	2000 miles, if the Moon is at apogee
B	500 miles, if the Moon is at perigee
C	5000 miles, if the Moon is at perigee
D	12,000 miles, if the Moon is visible by both stations

13. - E3B03

What is the best time of day for transequatorial propagation?

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

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The ratio of X-Ray flux to radio flux, correlated to sunspot number
B	UV emissions at 304 angstroms, correlated to solar flux index
C	The solar emission at 304 GHz, correlated to X-Ray flare levels
D	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity

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 frequency standard is displayed and the probe is adjusted until the deflection time is accurate
C	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
D	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate

16. - E4B11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Select	Answer
A	Loosely couple the antenna and a dummy load to the analyzer
B	Connect the analyzer via a high-impedance transformer to the antenna
C	Connect the antenna feed line directly to the analyzer's connector
D	Loosely couple the analyzer near the antenna base

17. - E4C15

What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Select	Answer
A	Detector noise
B	Induction motor noise
C	Atmospheric noise
D	Receiver front-end noise

18. - E4D13

Which of the following can cause receiver desensitization?

Select	Answer
A	Audio bias adjusted too high
B	Squelch gain misadjusted
C	Strong adjacent channel signals
D	Audio gain adjusted too low

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. - E5A15

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

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

21. - E5B06

What is susceptance?

Select	Answer
A	The inverse of reactance
B	A measure of the efficiency of a transformer
C	The magnetic impedance of a circuit
D	The ratio of magnetic field to electric field

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 3
B	Point 8
C	Point 5
D	Point 1

23. - E5D15

What is the power factor of an R-L circuit having a 45 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.707
C	0.5
D	1.0

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to emitter current
B	The change of base current with respect to collector current
C	The change of collector current with respect to gate current
D	The change of collector current with respect to base current

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Junction
B	Point contact
C	Zener
D	Tunnel

26. - E6C03

What is tri-state logic?

Select	Answer
A	Logic devices with 0, 1, and high impedance output states
B	Low power logic devices designed to operate at 3 volts
C	Proprietary logic devices manufactured by Tri-State Devices
D	Logic devices that utilize ternary math

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	RF susceptance would increase
B	Magnetic flux would increase with frequency
C	Harmonics and distortion could result
D	Temporary changes of the core permeability could result

28. - E6E01

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

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

29. - E6F07

What is a solid state relay?

Select	Answer
A	A mechanical relay that latches in the on or off state each time it is pulsed
B	A relay using transistors to drive the relay coil
C	A passive delay line
D	A device that uses semiconductors to implement the functions of an electromechanical relay

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It decodes a decimal number for display on a seven segment LED display
B	It adds two decimal numbers together
C	It produces ten output pulses for every input pulse
D	It produces one output pulse for every ten input pulses

31. - E7B08

How can an RF power amplifier be neutralized?

Select	Answer
A	By increasing the driving power
B	By reducing the driving power
C	By feeding a 180-degree out-of-phase portion of the output back to the input
D	By feeding an in-phase component of the output back to the input

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
B	A variable bandwidth crystal lattice filter
C	A special filter that emphasizes image responses
D	An automatic notch filter

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Prevention of battery damage due to overcharge
B	Prevention of battery undercharge
C	Matching of day and night charge rates
D	Control of electrolyte levels during battery discharge

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By driving a product detector with a DSB signal
B	By using a balanced modulator followed by a filter
C	By using a reactance modulator followed by a mixer
D	By using a loop modulator followed by a mixer

35. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	Mixing products are converted to voltages and subtracted by adder circuits
B	Emulation of quartz crystal filter characteristics
C	Combine signals with a quadrature phase relationship
D	A frequency synthesizer removes the unwanted sidebands

36. - E7G03

What is the typical input impedance of an integrated circuit op-amp?

Select	Answer
A	1000 ohms
B	Very low
C	100 ohms
D	Very high

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

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

38. - E8A04

What is "dither" with respect to analog to digital converters?

Select	Answer
A	A method of decimation by randomly skipping samples
B	An abnormal condition where the converter cannot settle on a value to represent the signal
C	An error caused by irregular quantization step size
D	A small amount of noise added to the input signal to allow more precise representation of a signal over time

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	0.167
C	1.67
D	60

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. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It is possible to transmit both upper and lower case text
B	It includes built in error correction features
C	It contains fewer information bits per character than any other code
D	It uses one character as a shift code to send numeric and special characters

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	Distance from the transmitter
B	The standing wave ratio
C	Soil conductivity
D	Take-off angle

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Elevation
B	Radiation resistance
C	Polarization
D	Azimuth

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band trap antenna
B	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
C	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
D	A phased array antenna consisting of multiple loops

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
B	An electrically short connection to a metal water pipe
C	A 50 ohm resistor connected to ground
D	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The stub match
B	The gamma match
C	The epsilon match
D	The delta match

47. - E9F11

What impedance does a 1/8 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	The same as the input impedance of the final generator stage
C	A capacitive reactance
D	An inductive reactance

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
B	It narrows the bandwidth of the received signal to improve signal to noise ratio
C	It compensates for the effects of an isotropic antenna, thereby improving directivity
D	It prevents receiver overload which could make it difficult to determine peaks or nulls

50. - E0A05

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

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

Figure E5-2

Figure E9-2