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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	1.5 kHz
B	170 Hz
C	2.8 kHz
D	60 Hz

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	3 miles
B	10 miles
C	1 mile
D	30 miles

3. - E1C07

What is meant by local control?

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

4. - E1D09

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

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

5. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Immediately terminate the candidate's examination
B	Warn the candidate that continued failure to comply will result in termination of the examination
C	Allow the candidate to complete the examination, but invalidate the results
D	Immediately terminate everyone's examination and close the session

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	All of these choices are correct
B	The transmission must not be used to obscure the meaning of any communication
C	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
D	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geostationary
B	LEO
C	Geomagnetic
D	HEO

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

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 440 MHz transceiver with a 9600 baud modem
B	A standard wireless router running custom software
C	A 2 meter VHF transceiver with a 1200 baud modem
D	An optical cable connection between the USB ports of 2 separate computers

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	JT65
B	PACTOR III
C	FSK441
D	Olivia

11. - E2E03

How is the timing of JT65 contacts organized?

Select	Answer
A	It depends on the lunar phase
B	Alternating transmissions at 1 minute intervals
C	Stations take turns on alternate days
D	By exchanging ACK/NAK packets

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

Select	Answer
A	Warm and cold fronts
B	Gray-line
C	Lightning discharges
D	Sprites and jets

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Around sunset
B	Early evening
C	Any time
D	Around sunrise

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	NVIS
B	Sporadic-E
C	Transequatorial propagation
D	Polar paths

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

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S11
B	S22
C	S12
D	S21

17. - E4C01

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

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

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	The off-frequency unwanted signal is heard in addition to the desired signal
B	A reduction in apparent signal strength
C	A large increase in background noise
D	The desired signal can no longer be heard

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

Select	Answer
A	All of these choices are correct
B	The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
C	The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
D	The interfering signal may drift slowly across the HF spectrum

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

Select	Answer
A	Resistance
B	Conductance
C	Capacitance
D	Resonance

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. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A positive phase angle
B	A negative real part
C	A positive real part
D	A negative phase angle

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Inductance
B	Permeability
C	Permittivity
D	Malleability

24. - E6A16

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

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

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a constant current source
B	As a high voltage rectifier
C	As a constant voltage source
D	As an RF detector

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

Select	Answer
A	The comparator changes its output state
B	The IC input can be damaged
C	The feedback loop becomes unstable
D	The comparator enters latch-up

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Thermal impedance
B	Permeability
C	Reactivity
D	Resistance

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

29. - E6F07

What is a solid state relay?

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

30. - E7A08

What logical operation does an OR gate perform?

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

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

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

32. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Select	Answer
A	A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
B	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
C	Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
D	An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output

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

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

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

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	Complex phasor representations
B	Higher data rate
C	Double-precision math routines
D	More taps

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	Undesired oscillations added to the desired signal
B	A reduction in high frequency response
C	An echo caused by a long time delay
D	Partial cancellation of the signal over a range of frequencies

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Toroidal inductors
B	Wirewound resistors
C	Non-inductive resistors
D	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. - 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	1/3
B	2000
C	3
D	6000

40. - E8C04

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

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

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
B	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
C	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
D	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

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

43. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below the guideline of 10 segments per half-wavelength?

Select	Answer
A	The resulting design will favor radiation of harmonic energy
B	The computed feed point impedance may be incorrect
C	The antenna will become mechanically unstable
D	Ground conductivity will not be accurately modeled

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	An omni-directional antenna commonly used for satellite communications
B	A dipole constructed from zip cord
C	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
D	An end fed dipole antenna

45. - E9D12

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

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

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To provide DC isolation between the feed line and the antenna
B	To provide a rejection notch that prevents the radiation of harmonics
C	To cancel the inductive reactance of the matching network
D	To transform the antenna impedance to a higher value

47. - E9F02

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

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

48. - E9G02

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

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

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It eliminates tracking errors caused by strong out-of-band signals
B	It allows stations to communicate without giving away their position
C	It is electro statically balanced against ground, giving better nulls
D	It automatically cancels ignition noise in mobile installations

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Advise your neighbors of the results of your tests
B	Make sure signals from your station are less than the uncontrolled MPE limits
C	Make sure signals from your station are less than the controlled MPE limits
D	You need only evaluate exposure levels on your own property