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	60 Hz
C	170 Hz
D	2.8 kHz

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

Select	Answer
A	The location is of geographical or horticultural importance
B	The location is near an area of political conflict
C	The location is in an ITU Zone designated for coordination with one or more foreign governments
D	The location is of environmental importance or significant in American history, architecture, or culture

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	You must bring a copy of FCC Public Notice DA 11-221
B	You must identify in the official language of the country in which you are operating
C	You must append "/CEPT" to your call sign
D	The U.S. embassy must approve of your operation

4. - E1D04

What is an Earth station in the amateur satellite service?

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

5. - E1E06

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

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

6. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and west of the U.S. Atlantic coastline
B	A line roughly parallel to and east of the U.S. Pacific coastline
C	A line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
D	A line roughly parallel to and south of the U.S.-Canadian border

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	50.0 MHz - 50.2 MHz
B	29.5 MHz - 29.7 MHz
C	435 MHz - 438 MHz
D	144 MHz - 146 MHz

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Hue
B	Spectral Intensity
C	Chroma
D	Luminance

9. - E2C05

What is the function of a DX QSL Manager?

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

10. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	AMTOR
B	AX.25
C	PACTOR
D	802.11

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. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	The energy propagates through a medium with a high refractive index
B	Electric and magnetic fields become aligned as they travel
C	The waves are reflected by the ionosphere and return to their source
D	Changing electric and magnetic fields propagate the energy

13. - E3B09

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

Select	Answer
A	Around the equinoxes, especially the fall equinox
B	Around the solstices, especially the summer solstice
C	Around the solstices, especially the winter solstice
D	Around the equinoxes, especially the spring equinox

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to aurora refraction
B	D-region skip
C	Downward bending due to density variations in the atmosphere
D	E-region skip

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

Select	Answer
A	It does not require an expensive high-precision time base
B	It can run on battery power for remote measurements
C	It can directly measure the modulation index of an FM transmitter
D	It provides improved resolution of low-frequency signals within a comparable time period

16. - E4B10

Which of the following describes a method to measure intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a logic analyzer
B	Modulate the transmitter with two non-harmonically related audio frequencies and observe the RF output with a spectrum analyzer
C	Modulate the transmitter with two non-harmonically related radio frequencies and observe the RF output with a spectrum analyzer
D	Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a peak reading wattmeter

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Frequency discrimination
B	Cross-modulation interference
C	Capture effect
D	Desensitization

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Raise the receiver IF frequency
B	Increase the receiver front end gain
C	Switch from fast AGC to slow AGC
D	Decrease the RF bandwidth of the receiver

19. - E4E06

What is a major cause of atmospheric static?

Select	Answer
A	Thunderstorms
B	Solar radio frequency emissions
C	Geomagnetic storms
D	Meteor showers

20. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

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

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

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

22. - E5C16

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

Select	Answer
A	Point 1
B	Point 7
C	Point 3
D	Point 8

23. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	To avoid unwanted inductive reactance
B	All of these choices are correct
C	To increase the thermal time constant
D	To maintain component lifetime

24. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The frequency at which the current gain is reduced to 1
B	The breakdown voltage of the base to collector junction
C	The switching speed of the transistor
D	The change in collector current with respect to base current

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Zero bias
B	Reverse bias
C	Forward bias
D	Inductive bias

26. - E6C03

What is tri-state logic?

Select	Answer
A	Logic devices that utilize ternary math
B	Logic devices with 0, 1, and high impedance output states
C	Proprietary logic devices manufactured by Tri-State Devices
D	Low power logic devices designed to operate at 3 volts

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	Magnetic flux would increase with frequency
B	Harmonics and distortion could result
C	Temporary changes of the core permeability could result
D	RF susceptance would increase

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

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
B	Optoisolators eliminate the effects of reflected light in the control circuit
C	Optoisolators provide a low impedance link between a control circuit and a power circuit
D	Optoisolators provide impedance matching between the control circuit and power circuit

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	An OR gate
B	A multiplexer
C	A flip-flop
D	An XOR gate

31. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	At a point where the load line intersects the zero bias current curve
B	Where the load line intersects the voltage axis
C	At a point where the bias resistor equals the load resistor
D	Approximately half-way between saturation and cutoff

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	A notch filter
B	An all-pass filter
C	A Pi-network filter
D	A band-pass filter

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Switching voltage regulator
B	Linear voltage regulator
C	Emitter follower
D	Grounded emitter amplifier

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	The sum, difference and square root of the input frequencies
B	1.414 and 0.707 times the input frequency
C	The two input frequencies along with their sum and difference frequencies
D	Two and four times the original frequency

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters delay all frequency components of the signal by the same amount
B	FIR filters can respond faster to impulses
C	FIR filters are easier to implement for a given set of passband rolloff requirements
D	All of these choices are correct

36. - E7G01

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

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

37. - E7H02

Which describes a microphonic?

Select	Answer
A	Changes in oscillator frequency due to mechanical vibration
B	Distortion caused by RF pickup on the microphone cable
C	An IC used for amplifying microphone signals
D	Excess loading of the microphone by an oscillator

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Phase reversal
B	Sequential sampling
C	Harmonic regeneration
D	Level shifting

39. - E8B07

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

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

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is only used for RTTY
B	Baud is twice the symbol rate
C	They are the same
D	Symbol rate is only used for packet-based modes

41. - E8D01

Why are received spread spectrum signals resistant to interference?

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

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
B	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
C	The combined losses of the antenna elements and feed line
D	The specific impedance of the antenna

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

Select	Answer
A	They are the same
B	The total amount of radiation from the directional antenna is increased by the gain of the antenna
C	The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
D	The total amount of radiation from the directional antenna is stronger by its front-to-back ratio

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 multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
D	A phased array antenna consisting of multiple loops

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	At a voltage node
B	As close to the transmitter as possible
C	As low as possible on the vertical radiator
D	Near the center of the vertical radiator

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	Pi-L-network
B	A series capacitor
C	A shunt inductor
D	Pi-network

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	All of these choices are correct
B	Foam dielectric has higher velocity factor
C	Foam dielectric has lower safe operating voltage limits
D	Foam dielectric has lower loss per unit of length

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radio propagation
B	Antenna radiation pattern
C	Impedance along transmission lines
D	Radiation resistance

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It is non-rotatable
B	It has a bidirectional pattern
C	It receives equally well in all directions
D	It is practical for use only on VHF bands

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

Select	Answer
A	By the odor
B	Any ordinary smoke detector can be used
C	Only with a carbon monoxide detector
D	By the yellowish appearance of the gas

Figure E5-2

Figure E7-3