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	3 kHz above the lower band edge
B	300 Hz above the lower band edge
C	1 kHz above the lower band edge
D	The exact lower band edge

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	A proposal must be submitted to the National Park Service
C	An Environmental Assessment must be submitted to the FCC
D	A letter of intent must be filed with the National Audubon Society

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

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	70 cm and 33 cm
B	33 cm and 13 cm
C	70 cm and 13 cm
D	70 cm only

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The FCC
B	Each administering VE
C	The VEC coordinating the session
D	The VE session manager

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

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

Select	Answer
A	To avoid interfering with terrestrial QSOs
B	To avoid reducing the downlink power to all other users
C	To prevent creating errors in the satellite telemetry
D	To prevent the satellite from emitting out-of-band signals

8. - E2B15

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

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

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A method of exchanging information during a contest QSO
B	The rules of order for meetings between contest sponsors
C	The most common set of contest rules
D	A standard for submission of electronic contest logs

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Multi-satellite relaying
B	Node hopping
C	Store-and-forward
D	Digipeating

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	316 Hz
B	550 Hz
C	31 Hz
D	2.16 kHz

12. - E3A13

Which emission mode is best for aurora propagation?

Select	Answer
A	SSB
B	FM
C	RTTY
D	CW

13. - E3B03

What is the best time of day for transequatorial propagation?

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

14. - E3C01

What does the term ray tracing describe in regard to radio communications?

Select	Answer
A	Evaluating high voltage sources for X-Rays
B	The process in which an electronic display presents a pattern
C	Modeling a radio wave's path through the ionosphere
D	Determining the radiation pattern from an array of antennas

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Analog-to-digital conversion speed of the soundcard
B	Amount of memory on the soundcard
C	Q of the interface of the interface circuit
D	All of these choices are correct

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Time base accuracy
B	Input attenuator accuracy
C	Temperature coefficient of the logic
D	Decade divider accuracy

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

Select	Answer
A	RAM speed used for data storage
B	CPU register width in bits
C	Analog-to-digital converter sample width in bits
D	Anti-aliasing input filter bandwidth

18. - E4D02

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

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

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	A defective doorbell or doorbell transformer inside a nearby residence
B	Arcing contacts in a thermostatically controlled device
C	A malfunctioning illuminated advertising display
D	All of these choices are correct

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	218.3 kHz
B	31.4 kHz
C	436.6 kHz
D	15.7 kHz

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	One time constant
B	One discharge period
C	An exponential discharge rate of one
D	A discharge factor of one

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By Y and G values
B	By phase angle and amplitude
C	By X and R values
D	By real and imaginary parts

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

Select	Answer
A	0.577
B	0.866
C	1.73
D	0.5

24. - E6A17

What are the names of the three terminals of a field-effect transistor?

Select	Answer
A	Gate, drain, source
B	Emitter, base 1, base 2
C	Emitter, base, collector
D	Gate 1, gate 2, drain

25. - E6B11

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

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

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A device to control industrial equipment
B	An algorithm for simulating logic functions during circuit design
C	Programmable equipment used for testing digital logic integrated circuits
D	A programmable collection of logic gates and circuits in a single integrated circuit

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

28. - E6E08

How is voltage from a power supply normally furnished to the most common type of monolithic microwave integrated circuit (MMIC)?

Select	Answer
A	MMICs require no operating bias
B	Through a capacitor and RF choke connected to the amplifier input lead
C	Through a resistor and/or RF choke connected to the amplifier output lead
D	Directly to the bias voltage (VCC IN) lead

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The relative fraction of light that is converted to current
B	The effective payback period
C	The open-circuit voltage divided by the short-circuit current under full illumination
D	The output RF power divided by the input DC power

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It only produces logic "0" at its output when all inputs are logic "1"
B	It produces logic "0" at its output if all inputs are logic "1"
C	It produces logic "1" at its output if any or all inputs are logic "1"
D	It produces logic "1" at its output if all inputs are logic "0"

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

Select	Answer
A	Less than 180 degrees
B	More than 180 degrees but less than 360 degrees
C	The entire cycle
D	Exactly 180 degrees

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Pi
B	Cascode
C	Pi-L
D	Omega

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	It has a ramp voltage as its output
B	The control element duty cycle is proportional to the line or load conditions
C	The conduction of a control element is varied to maintain a constant output voltage
D	It eliminates the need for a pass transistor

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

Select	Answer
A	An automatic band-switching circuit
B	A circuit for detecting FM signals
C	A circuit for filtering two closely adjacent signals
D	An FM generator circuit

35. - E7F01

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

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

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

Select	Answer
A	Restrict both gain and Q
B	Restrict Q but increase gain
C	Restrict gain but increase Q
D	Increase both gain and Q

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Mechanically isolating the oscillator circuitry from its enclosure
B	Eliminating noise on the oscillator's power supply
C	Using the oscillator only for CW and digital signals
D	Use of NP0 capacitors

38. - E8A06

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

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

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 digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
D	A bandwidth compression technique using Fourier transforms

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	Special binary codes provide automatic correction
B	If errors are detected, a retransmission is requested
C	If errors are detected, redundant data is substituted
D	Special polynomial codes provide automatic correction

41. - E8D09

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

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

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

43. - E9B12

What is the far field of an antenna?

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

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
B	A wideband vertical antenna constructed from precisely tapered aluminum tubing
C	A portable antenna erected using two push support poles
D	An end fed folded dipole antenna

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

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 epsilon match
B	The stub match
C	The delta match
D	The gamma match

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

Select	Answer
A	The termination impedance
B	The center conductor resistivity
C	The line length
D	Dielectric materials used in the line

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning reactance values with regard to the resistance axis
B	Reassigning prime center with regard to the reactance axis
C	Reassigning resistance values with regard to the reactance axis
D	Reassigning impedance values with regard to the prime center

49. - E9H11

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

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

50. - E0A05

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

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