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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operator of the originating station
B	The control operators of all the stations in the system not authenticating the source from which they accept communications
C	The control operator of the packet bulletin board station
D	The control operators of all the stations in the system

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

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

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
B	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	All HF bands

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

Select	Answer
A	Have each applicant sign an affidavit stating that all session rules were followed
B	Use a real-time video link and the Internet to connect the exam session to the observing VEs
C	The exam proctor observes the applicants and reports any violations
D	Record the exam session on video tape for later review by the VE team

6. - E1F04

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

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

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of the satellite's low orbital altitude
B	Because the satellite is spinning
C	Because of the Doppler Effect
D	Because of ionospheric absorption

8. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To lock the color burst oscillator in color SSTV images
B	To identify the call sign of the station transmitting
C	To provide vertical synchronization
D	To identify the SSTV mode being used

9. - E2C10

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

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

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Polar coordinates
B	Latitude and longitude
C	Radio direction finding spectrum analysis
D	Time and frequency

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK uses a DC-coupled data connection
B	Audio FSK has a superior frequency response
C	Direct FSK applies the data signal to the transmitter VFO
D	Audio FSK can be performed anywhere in the transmit chain

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Temperature inversion
B	The jet stream
C	Wind shear
D	Dust devil

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	80 meters
B	20 meters
C	6 meters
D	10 meters

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Increasing disruption of the geomagnetic field
B	Higher levels of solar UV radiation
C	Decreasing disruption of the geomagnetic field
D	An increase in the critical frequency

15. - E4A15

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

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

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
B	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
C	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
D	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	4.2 kHz
B	4.8 kHz
C	2.4 kHz
D	1 kHz

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
B	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor
C	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
D	The difference in dB between the noise floor and the third order intercept point

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	All of these choices are correct
B	A malfunctioning illuminated advertising display
C	A defective doorbell or doorbell transformer inside a nearby residence
D	Arcing contacts in a thermostatically controlled device

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

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	B
B	X
C	G
D	Y

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

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

23. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

Select	Answer
A	50 watts
B	400 watts
C	2000 watts
D	80 watts

24. - E6A04

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

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

25. - E6B04

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

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

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A programmable collection of logic gates and circuits in a single integrated circuit
B	Programmable equipment used for testing digital logic integrated circuits
C	An algorithm for simulating logic functions during circuit design
D	A device to control industrial equipment

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

Select	Answer
A	Ceramic
B	Ferrite
C	Brass
D	Powdered-iron

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	50 ohms
B	450 ohms
C	10 ohms
D	300 ohms

29. - E6F07

What is a solid state relay?

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

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It stores one bit of data in either a 0 or 1 state
B	It switches momentarily to the opposite binary state and then returns to its original state after a set time
C	It maintains a constant output voltage, regardless of variations in the input voltage
D	It produces a continuous square wave oscillating between 1 and 0

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Signal inversion
B	Increased overall intelligibility
C	Reduced intermodulation products
D	Signal distortion and excessive bandwidth

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 capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
B	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
C	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
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. - E7D08

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

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

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce AM signals
B	By varying the tuning of an amplifier tank circuit to produce AM signals
C	By varying the tuning of a microphone preamplifier to produce PM signals
D	By varying the tuning of an amplifier tank circuit to produce PM signals

35. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

Select	Answer
A	Sample clock phase noise
B	Sample rate
C	Sample width in bits
D	Processor latency

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
B	The output voltage of the op-amp minus its input voltage
C	The potential between the amplifier input terminals of the op-amp in an open loop condition
D	The differential input voltage needed to bring the open loop output voltage to zero

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit consisting of a precision push-pull amplifier with a differential input
B	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
C	An electronic circuit also known as a monostable multivibrator
D	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference 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. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	1000
B	0.3
C	3
D	3000

40. - E8C09

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

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

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	High-pass filters at the transmitter output
B	Increase keying waveform rise and fall times
C	Low-pass filters at the transmitter output
D	Reduce keying waveform rise and fall times

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It decreases
B	It is essentially unaffected
C	It increases geometrically
D	It increases arithmetically

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of segments, each having a distinct value of voltage across it
B	A wire is modeled as a single sine-wave current generator
C	A wire is modeled as a series of points, each having a distinct location in space
D	A wire is modeled as a series of segments, each having a uniform value of current

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It reduces losses in the radiating portion of the antenna
B	It reduces low-angle radiation
C	It causes increased SWR
D	It changes the impedance angle of the matching network

45. - E9D03

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

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

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
B	The driven element resonance must be lower than the operating frequency
C	The driven element reactance must be inductive
D	The driven element reactance must be capacitive

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	Electrical signals move more slowly in a coaxial cable than in air
B	The characteristic impedance is higher in a parallel feed line
C	The surge impedance is higher in a parallel feed line
D	Skin effect is less pronounced in the coaxial cable

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Points with constant resistance
B	SWR
C	Frequency
D	Points with constant reactance

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	A fixed receiving station plots three headings to the signal source
B	A fixed receiving station uses three different antennas to plot the location of the signal source
C	Antenna headings from several different receiving locations are used to locate the signal source
D	The geometric angles of sky waves from the source are used to determine its position

50. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Select	Answer
A	Polyethylene
B	Polymorphic silicon
C	Polychlorinated Biphenyls
D	Polytetrafluroethylene

Figure E5-2

Figure E7-3