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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A14

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

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

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

3. - E1C04

What is meant by IARP?

Select	Answer
A	A forecast of intermittent aurora radio propagation
B	An indication of increased antenna reflected power
C	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
D	The internal amateur radio practices policy of the FCC

4. - E1D01

What is the definition of the term telemetry?

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

5. - E1E03

What is a Volunteer Examiner Coordinator?

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

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 satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
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 be capable of external RF switching between its input and output networks

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The point of minimum height of a satellite's orbit
B	The time it takes for a satellite to complete one revolution around the Earth
C	The point of maximum height of a satellite's orbit
D	The time it takes for a satellite to travel from perigee to apogee

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	None; they are allowed on all amateur frequencies
B	They are not permitted above 54 MHz
C	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
D	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz

9. - E2C05

What is the function of a DX QSL Manager?

Select	Answer
A	To relay calls to and from a DX station
B	To run a net to allow many stations to contact a rare DX station
C	To allocate frequencies for DXpeditions
D	To handle the receiving and sending of confirmation cards for a DX station

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	High speed CW identification to avoid fading
B	Judging optimum transmission times by monitoring beacons reflected from the Moon
C	Time synchronous transmissions alternately from each station
D	Storing and forwarding digital messages

11. - E2E05

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

Select	Answer
A	RTTY
B	PSK31
C	MFSK
D	Winlink

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A fluttery irregular fading
B	A gradual loss of signal as the Sun rises
C	A slow change in the pitch of the CW signal
D	The returning echo is several Hertz lower in frequency than the transmitted signal

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	6 meters to 2 meters
D	160 meters to 40 meters

14. - E3C06

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

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

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Bit error rate tester
B	Modulation monitor
C	Logic analyzer
D	Network analyzer

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It can display results directly in Smith chart format
B	It is relatively immune to drift in the signal generator source
C	It is very precise in obtaining a signal null
D	It provides an excellent match under all conditions

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise
B	The ratio of atmospheric noise to phase noise
C	The ratio of thermal noise to atmospheric noise
D	The ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A properly terminated circulator at the output of the transmitter
B	A Class D final amplifier
C	A band-pass filter in the feed line between the transmitter and receiver
D	A Class C final amplifier

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Broadband white noise
B	Ignition noise
C	All of these choices are correct
D	Power line noise

20. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	Maximum
B	R/L
C	L/R
D	Minimum

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	B
B	X
C	G
D	Y

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Faraday grid
B	Rectangular coordinates
C	Maidenhead grid
D	Elliptical coordinates

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as kinetic energy in the circuit
B	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
C	It is dissipated in the formation of inductive and capacitive fields
D	It is dissipated as heat in the circuit

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	Superconductor-type
B	Bipolar-type
C	N-type
D	P-type

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	A large region of intrinsic material
B	Extremely high reverse breakdown voltage
C	Reverse bias controls its forward voltage drop
D	Ability to dissipate large amounts of power

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

Select	Answer
A	3
B	4
C	1
D	2

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
C	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
D	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel

28. - E6E01

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

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

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of electrical energy to mechanical energy
B	The tendency of a battery to discharge when used outside
C	The conversion of light to electrical energy
D	The conversion of voltage to current when exposed to light

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	A clock
B	An "AND" gate
C	A flip-flop
D	An "OR" gate

31. - E7B13

In Figure E7-2, what is the purpose of R?

Select	Answer
A	Collector load
B	Fixed bias
C	Voltage regulation
D	Emitter load

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	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
B	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
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. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	The controlled device's duty cycle is changed to produce a constant average output voltage
B	It gives a ramp voltage at its output
C	It is generally less efficient than a linear regulator
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 breakdown of the Zener voltage
C	By mixing signals with noise in the transition region of the diode
D	By rectification and filtering of RF signals

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 phase-inverting filter
B	A crystal-lattice filter
C	An adaptive 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	28
B	0.07
C	7
D	14

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Provide the crystal with a specified parallel capacitance
B	Bias the crystal at a specified voltage
C	Provide the crystal with a specified parallel inductance
D	Bias the crystal at a specified current

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	All of these choices are correct
D	Lower the input bandwidth to increase the effective resolution

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It increases as the RF carrier frequency increases
B	It decreases as the RF carrier frequency increases
C	It varies with the square root of the RF carrier frequency
D	It does not depend on the RF carrier frequency

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It has more resolution than simple binary
B	It has more possible states than simple binary
C	It facilitates error detection
D	It increases security

41. - E8D01

Why are received spread spectrum signals resistant to interference?

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

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. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	Antenna gain
B	Polar plots of the far field elevation and azimuth patterns
C	All of these choices are correct
D	SWR vs frequency charts

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Higher losses
B	Greater structural strength
C	Improved radiation efficiency
D	Lower Q

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The stub matching system
B	The delta matching system
C	The gamma matching system
D	The omega matching system

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	0.2 meters
B	3.5 meters
C	20 meters
D	2.3 meters

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Radiation-pattern circles
B	Coaxial-length circles
C	Standing wave ratio circles
D	Antenna-length circles

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A large circularly polarized antenna
B	A vertical antenna coupled to a feed line through an inductive loop of wire
C	One or more turns of wire wound in the shape of a large open coil
D	A small coil of wire tightly wound around a toroidal ferrite core

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Mica
B	Uranium Hexafluoride
C	Zinc oxide
D	Beryllium Oxide

Figure E6-5

Figure E7-2

Figure E7-4