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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	1 kHz below the upper band edge
B	The exact upper band edge
C	300 Hz below the upper band edge
D	3 kHz below the upper band edge

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	Specific local government channels
B	Military Auxiliary Radio System (MARS) channels
C	All amateur service frequencies authorized to the control operator
D	Specific segments in the amateur service MF, HF, VHF and UHF bands

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	3 minutes
B	30 seconds
C	10 minutes
D	5 minutes

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station that transmits telemetry consisting of measurements of upper atmosphere
B	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
C	An amateur station located more than 50 km above the Earth's surface
D	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 77%
B	Minimum passing score of 74%
C	Minimum passing score of 80%
D	Minimum passing score of 70%

6. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications transmitted for hire or material compensation, except as otherwise provided in the rules
B	Communications that have a religious content
C	Communications that have a political content, except as allowed by the Fairness Doctrine
D	Communications in a language other than English

7. - E2A04

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

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

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	3 KHz
B	10 KHz
C	15 KHz
D	20 KHz

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To separate the calling stations from the DX station
B	To improve operating efficiency by reducing interference
C	All of these choices are correct
D	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations

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	Digipeating
C	Node hopping
D	Store-and-forward

11. - E2E03

How is the timing of JT65 contacts organized?

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

12. - E3A05

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

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

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Successive ionospheric reflections without an intermediate reflection from the ground
B	Propagation across the geomagnetic equator
C	Propagation away from the great circle bearing between stations
D	Signals reflected back toward the transmitting station

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class B
B	Class A
C	Class X
D	Class M

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

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

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

Select	Answer
A	The transmitter is not properly neutralized
B	There is possibly a short to ground in the feed line
C	There is an impedance mismatch between the antenna and feed line
D	There is more power going into the antenna

17. - E4C15

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

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

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	The third-order intercept is much higher than other orders
B	Third-order intermodulation produces three products for every input signal within the band of interest
C	Third-order products are an indication of poor image rejection
D	The third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E07

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

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

20. - E5A02

What is resonance in an electrical circuit?

Select	Answer
A	The highest frequency that will pass current
B	The frequency at which the capacitive reactance equals the inductive reactance
C	The lowest frequency that will pass current
D	The frequency at which the reactive impedance equals the resistive impedance

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	76 degrees with the voltage lagging the current
B	14 degrees with the voltage leading the current
C	14 degrees with the voltage lagging the current
D	76 degrees with the voltage leading the current

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Far field diagram
B	Near field diagram
C	Venn diagram
D	Phasor diagram

23. - E5D08

What type of energy is stored in an electromagnetic or electrostatic field?

Select	Answer
A	Potential energy
B	Electromechanical energy
C	Kinetic energy
D	Thermodynamic energy

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Acceptor impurity
B	Insulator impurity
C	N-type impurity
D	Donor impurity

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant current drop under conditions of varying voltage
B	An internal capacitance that varies with the applied voltage
C	A constant voltage drop under conditions of varying current
D	A negative resistance region

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	The input switching threshold is about one-half the power supply voltage
B	Input signals are stronger
C	The input switching threshold is about two times the power supply voltage
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	Inductive kickback
B	Inter-turn capacitance
C	Non-linear core hysteresis
D	The skin effect

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Gallium nitride
B	Silicon nitride
C	Silicon
D	Silicon dioxide

29. - E6F07

What is a solid state relay?

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

30. - E7A02

What is the function of a decade counter digital IC?

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

31. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

Select	Answer
A	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
B	The tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
C	The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
D	The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current

32. - E7C09

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

Select	Answer
A	A special filter that emphasizes image responses
B	An automatic notch filter
C	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
D	A variable bandwidth crystal lattice filter

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To balance the low-voltage filament windings
B	To cut down on waste heat generated by the power supply
C	To improve output voltage regulation
D	To boost the amount of output 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 rectification and filtering of RF signals
D	By mixing signals with noise in the transition region of the diode

35. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	Provide incremental signal delays for filter algorithms
B	Provide access for debugging software
C	To reduce excess signal pressure levels
D	Select the point at which baseband signals are generated

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 gain but increase Q
C	Increase both gain and Q
D	Restrict Q but increase gain

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

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

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The degree of carrier suppression
B	The amplifier gain
C	The characteristics of the modulating signal
D	The frequency of the modulating signal

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	The transmitted signal jumps from band to band at a predetermined rate
C	Two or more information streams are merged into a baseband, which then modulates the transmitter
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Gray code
C	Extended Binary Coded Decimal Interchange Code
D	Excess 3 code

41. - E8D12

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

Select	Answer
A	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
B	Faster transmission rate
C	Foreign language characters can be sent
D	The signal can overpower interfering signals

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

Select	Answer
A	To calculate the front-to-side ratio of the antenna
B	To calculate the front-to-back ratio of the antenna
C	To match impedances in order to minimize standing wave ratio on the transmission line
D	To measure the near-field radiation density from a transmitting antenna

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

Select	Answer
A	75 degrees
B	50 degrees
C	25 degrees
D	30 degrees

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The horizontal beam width decreases with height
B	The horizontal beam width increases with height
C	The main lobe takeoff angle increases with increasing height
D	The main lobe takeoff angle decreases with increasing height

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

Select	Answer
A	To swamp out harmonics
B	To minimize the Q
C	To minimize losses
D	To maximize losses

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	Double-bazooka match
B	All of these choices are correct
C	Gamma match
D	Hairpin match

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	Very low impedance
B	The same as the input impedance to the generator
C	Very high impedance
D	The same as the characteristic impedance of the line

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Reactance axis
B	Prime axis
C	Impedance axis
D	Polar axis

49. - E9H09

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

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

50. - E0A05

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

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

Figure E9-1

Figure E9-3