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

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	An amateur station transmission made at random without the proper call sign identification
B	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
C	Any transmitted signal that unintentionally interferes with another licensed radio station
D	A signal transmitted to prevent its detection by any station other than the intended recipient

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	CEPT agreement
B	All of these choices are correct
C	ITU reciprocal license
D	IARP agreement

4. - E1D03

What is a telecommand station in the amateur satellite service?

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

5. - E1E06

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

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

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	It was imported from a manufacturer in another country and was certificated by that country's government
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
D	The equipment dealer assembled it from a kit

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 ionospheric absorption
D	Because of the Doppler Effect

8. - E2B04

What is blanking in a video signal?

Select	Answer
A	Synchronization of the horizontal and vertical sync pulses
B	Turning off the scanning beam at the conclusion of a transmission
C	Turning off the scanning beam while it is traveling from right to left or from bottom to top
D	Transmitting a black and white test pattern

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	30 m
B	2 m
C	6 m
D	33 cm

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	Hellschreiber
B	FSK441
C	APRS
D	WSPR

11. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	PACTOR
B	Hellschreiber
C	RTTY
D	AMTOR

12. - E3A10

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

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

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become elliptically polarized
B	They become phase-locked
C	Their polarization is randomly modified
D	They are bent toward the magnetic poles

14. - E3C01

What does the term ray tracing describe in regard to radio communications?

Select	Answer
A	The process in which an electronic display presents a pattern
B	Determining the radiation pattern from an array of antennas
C	Evaluating high voltage sources for X-Rays
D	Modeling a radio wave's path through the ionosphere

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
B	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
C	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	75 watts
B	25 watts
C	125 watts
D	100 watts

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Loss of sensitivity
B	Distortion
C	Overload
D	Excess output level

18. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

Select	Answer
A	Squelch gain rollback
B	Desensitization
C	Cross-modulation interference
D	Quieting

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
B	You are receiving sky wave signals from a distant station
C	Your station receiver IF amplifier stage is defective
D	The broadcast station is transmitting an over-modulated signal

20. - E5A09

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

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

21. - E5B05

What happens to the magnitude of a reactance when it is converted to a susceptance?

Select	Answer
A	The sign is reversed
B	The magnitude of the susceptance is the reciprocal of the magnitude of the reactance
C	It is shifted by 90 degrees
D	It is unchanged

22. - E5C05

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

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

23. - E5D01

What is the result of skin effect?

Select	Answer
A	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface
B	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
C	Thermal effects on the surface of the conductor increase the impedance
D	Thermal effects on the surface of the conductor decrease the impedance

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of base current with respect to collector current
B	The change of collector current with respect to base current
C	The change of collector current with respect to gate current
D	The change of collector current with respect to emitter current

25. - E6B13

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

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

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	Its simplicity results in much less expensive devices than standard CMOS
B	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
C	All of these choices are correct
D	It is totally immune to electrostatic damage

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

Select	Answer
A	13 turns
B	79 turns
C	141 turns
D	35 turns

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	DIP
B	Ball grid array
C	SOT
D	PLCC

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It stays the same
B	It decreases
C	It increases
D	It becomes unstable

30. - E7A06

What is a characteristic of a monostable multivibrator?

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

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they are relatively far in frequency from the desired signal
B	Because they are relatively close in frequency to the desired signal
C	Because they maintain the sidebands, thus causing multiple duplicate signals
D	Because they invert the sidebands causing distortion

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A Butterworth filter
B	A Chebyshev filter
C	An active LC filter
D	A passive op-amp filter

33. - E7D12

What is the drop-out voltage of an analog voltage regulator?

Select	Answer
A	Minimum input voltage for rated power dissipation
B	Maximum amount that the output voltage may decrease at rated load
C	Minimum input-to-output voltage required to maintain regulation
D	Maximum amount that the output voltage drops when the input voltage is varied over its specified range

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a loop modulator followed by a mixer
B	By using a reactance modulator followed by a mixer
C	By using a balanced modulator followed by a filter
D	By driving a product detector with a DSB signal

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

Select	Answer
A	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
B	Incoming RF is converted to a control voltage for a voltage controlled oscillator
C	A switching mixer is used to generate I and Q signals directly from the RF input
D	Software is converted from source code to object code during operation of the receiver

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

Select	Answer
A	1
B	76
C	38
D	0.03

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a reference oscillator and the output waveform
B	The phase relationship between a voltage-controlled oscillator and the output waveform
C	The synthesizer frequency limits and frequency values stored in the radio memories
D	The amplitude values that represent a sine-wave output

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Numerical analysis
B	Vector analysis
C	Fourier analysis
D	Differential analysis

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
B	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
C	Two or more signals are quadrature modulated to increase bandwidth efficiency
D	Two or more signals are arranged to share discrete time slots of a data transmission

40. - E8C11

What is the relationship between symbol rate and baud?

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

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	Strong ALC action
B	Rapid signal fading
C	High reflected power
D	Harmonics on higher bands

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	Soil conductivity
C	Take-off angle
D	The standing wave ratio

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	7
B	3
C	1
D	4

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

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

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain does not change
B	Gain increases by 3 dB
C	Gain increases by 6 dB
D	Gain is multiplied by 0.707

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Use the universal stub matching technique
B	Connect a parallel-resonant LC network across the antenna feed terminals
C	Connect a series-resonant LC network across the antenna feed terminals
D	Use a 50 ohm 1:1 balun between the antenna and feed line

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 characteristic impedance of the line
C	Very high impedance
D	The same as the input impedance to the generator

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H09

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

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

50. - E0A10

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

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

Figure E7-4

Figure E9-2