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	60 Hz
D	2.8 kHz

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. - E1C01

What is a remotely controlled station?

Select	Answer
A	A station operated away from its regular home location
B	A station controlled by someone other than the licensee
C	A station operating under automatic control
D	A station controlled indirectly through a control link

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station that transmits telemetry consisting of measurement of upper atmosphere
B	An amateur station that is not able to communicate using amateur satellites
C	Any amateur station on the surface of the Earth
D	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space

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. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The satellite's uplink and downlink frequency bands
B	The type of signals that can be relayed through the satellite
C	The satellite's orientation with respect to the Earth
D	Whether the satellite is in a polar or equatorial orbit

8. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	A special notch filter to remove synchronization pulses
B	A special IF converter
C	A special front end limiter
D	No other hardware is needed

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Repeater contacts between U.S. club members
B	Contacts between a U.S. station and a non-U.S. station
C	Special event contacts between stations in the U.S.
D	Contacts using tactical call signs

10. - E2D12

How does JT65 improve EME communications?

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

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	RTTY
B	MT63
C	PSK31
D	PACTOR

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	Rain droplets must be electrically charged
B	Rain droplets must be within the E layer
C	The rain must be within radio range of both stations
D	All of these choices are correct

13. - E3B03

What is the best time of day for transequatorial propagation?

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

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	Sporadic-E
B	Polar paths
C	NVIS
D	Transequatorial propagation

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	All of these choices are correct
B	Never use a high impedance probe to measure a low impedance circuit
C	Keep the signal ground connection of the probe as short as possible
D	Never use a DC-coupled probe to measure an AC circuit

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	Frequency order of the measurements
B	Relative quality of the data
C	The relative time between measurements
D	The port or ports at which measurements are made

17. - E4C02

Which of the following portions of a receiver can be effective in eliminating image signal interference?

Select	Answer
A	A front-end filter or pre-selector
B	A narrow IF filter
C	A properly adjusted product detector
D	A notch filter

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

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By observing the AC power line waveform with an oscilloscope
B	By observing the AC power line voltage with a spectrum analyzer
C	By checking the power line voltage with a time domain reflectometer
D	By turning off the AC power line main circuit breaker and listening on a battery operated radio

20. - E5A10

How is the Q of an RLC series resonant circuit calculated?

Select	Answer
A	Resistance divided by the reactance of either the inductance or capacitance
B	Reactance of either the inductance or capacitance times the resistance
C	Reactance of either the inductance or capacitance divided by the resistance
D	Reactance of the inductance times the reactance of the capacitance

21. - E5B09

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

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

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The coordinate values along the horizontal and vertical axes
B	The tangent and cotangent values
C	The magnitude and phase of the point
D	The sine and cosine values

23. - E5D04

Why are short connections necessary at microwave frequencies?

Select	Answer
A	Because of ground reflections
B	To reduce phase shift along the connection
C	To increase neutralizing resistance
D	To reduce noise figure

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Corner frequency
B	Beta cutoff frequency
C	Alpha rejection frequency
D	Alpha cutoff frequency

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Tunnel diode
B	Zener diode
C	Silicon-controlled rectifier
D	Varactor diode

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	Complex logic functions can be created in a single integrated circuit
B	Many similar gates are less expensive than a mixture of gate types
C	A PGA contains its own internal power supply
D	All of these choices are correct

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Direct current
B	Stabilizing current
C	Magnetizing current
D	Excitation current

28. - E6E01

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

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

29. - E6F09

What is the efficiency of a photovoltaic cell?

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

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	4
B	8
C	2
D	1

31. - E7B01

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

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

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

Select	Answer
A	A Pi-network with an additional series inductor on the output
B	A network with only three discrete parts
C	A Phase Inverter Load network
D	A matching network in which all components are isolated from ground

33. - E7D09

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

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

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. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	An adaptive filter
B	A Hilbert-transform filter
C	A phase-inverting filter
D	A crystal-lattice filter

36. - E7G03

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

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

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a capacitive divider
C	Through link coupling
D	Through a tapped coil

38. - E8A04

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

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

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	EME
B	Extremely low-power contacts
C	OFDM signals are not allowed on amateur bands
D	High speed digital modes

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 26 Hz
B	Approximately 52 Hz
C	Approximately 13 Hz
D	Approximately 104 Hz

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	Faster transmission rate
B	The signal can overpower interfering signals
C	Foreign language characters can be sent
D	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth

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	Soil conductivity
C	Distance from the transmitter
D	The standing wave ratio

43. - E9B03

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-side ratio?

Select	Answer
A	18 dB
B	12 dB
C	24 dB
D	14 dB

44. - E9C09

What is a G5RV antenna?

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

45. - E9D07

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

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

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	An SWR greater than 1:1
B	An SWR less than 1:1
C	A reflection coefficient greater than 1
D	A dielectric constant greater than 1

47. - E9F07

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

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

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	Antenna-length circles
D	Standing wave ratio circles

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By reducing the permeability of the loop shield
B	By increasing the number of wire turns in the loop and reducing the area of the loop structure
C	By increasing either the number of wire turns in the loop or the area of the loop structure or both
D	By winding adjacent turns in opposing directions

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Reduce received noise
B	Lightning protection
C	Reduce RFI to telephones and home entertainment systems
D	Reduce RF current flow between pieces of equipment

Figure E9-1