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

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	Any transmitted signal that unintentionally interferes with another licensed radio station
C	A signal transmitted to prevent its detection by any station other than the intended recipient
D	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C09

Which of these ranges of frequencies is available for an automatically controlled repeater operating below 30 MHz?

Select	Answer
A	29.500 MHz - 29.700 MHz
B	10.100 MHz - 10.150 MHz
C	24.940 MHz - 24.990 MHz
D	18.110 MHz - 18.168 MHz

4. - E1D03

What is a telecommand station in the amateur satellite service?

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

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
B	Photocopy all examination documents and forward them to the FCC for processing
C	Issue the examinee the new or upgrade license
D	All these choices are correct

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	The equipment dealer assembled it from a kit
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	It was imported from a manufacturer in another country and was certificated by that country's government

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	A log-periodic dipole array
B	A circularly polarized antenna
C	A linearly polarized antenna
D	An isotropic antenna

8. - E2B04

What is blanking in a video signal?

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

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	/R# where # is the district of the remote station
B	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
C	The ARRL section of the remote station
D	No additional indicator is required

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	PACTOR III
B	JT65
C	FSK441
D	Olivia

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	Automatic
B	Remote
C	ALE can use any type of control
D	Local

12. - E3A10

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

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

13. - E3B06

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

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

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately four times the distance
B	By approximately twice the distance
C	By approximately 50 percent of the distance
D	By approximately 15 percent of the distance

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

Select	Answer
A	It depends on how the data is stored internally
B	One-tenth the sample rate
C	The same as the sample rate
D	One-half the sample rate

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	25 watts
B	75 watts
C	125 watts
D	100 watts

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

Select	Answer
A	-148 dBm
B	-174 dBm
C	-164 dBm
D	-155 dBm

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

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Power line noise
B	Ignition noise
C	All of these choices are correct
D	Broadband white noise

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

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Elliptical coordinates
B	Faraday grid
C	Rectangular coordinates
D	Maidenhead grid

23. - E5D14

What is reactive power?

Select	Answer
A	Power consumed in circuit Q
B	Power consumed in wire resistance in an inductor
C	Power lost because of capacitor leakage
D	Wattless, nonproductive power

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 emitter current
C	The change of collector current with respect to gate current
D	The change of collector current with respect to base current

25. - E6B08

Which of the following describes a type of semiconductor diode?

Select	Answer
A	Thermionic emission diode
B	CMOS-field effect
C	Electrolytic rectifier
D	Metal-semiconductor junction

26. - E6C08

In Figure E6-5, what is the schematic symbol for a NAND gate?

Select	Answer
A	4
B	3
C	2
D	1

27. - E6D03

Which of the following is an aspect of the piezoelectric effect?

Select	Answer
A	Mechanical deformation of material by the application of a voltage
B	Generation of electrical energy in the presence of light
C	Increased conductivity in the presence of light
D	Mechanical deformation of material by the application of a magnetic field

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 dioxide
D	Silicon

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Copper oxide
B	Silicon
C	Cadmium Sulfide
D	Selenium

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	An "AND" gate
B	A clock
C	A flip-flop
D	An "OR" gate

31. - E7B17

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

Select	Answer
A	Because they invert the sidebands causing distortion
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 are relatively far in frequency from the desired signal

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Pi
B	Pi-L
C	Cascode
D	Omega

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To allow for remote control of the power supply
B	To allow the filter capacitors to charge gradually
C	To provide a dual-voltage output for reduced power applications
D	To compensate for variations of the incoming line voltage

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	Automatic limiting occurs
B	A beat frequency is generated
C	Mixer blanking occurs
D	Spurious mixer products are generated

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	A Hilbert-transform filter
B	A notch filter
C	An adaptive filter
D	An elliptical filter

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

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A direct digital synthesizer
B	A diode-switching matrix synthesizer
C	A hybrid synthesizer
D	A phase locked loop synthesizer

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A sawtooth wave
B	A cosine wave
C	A square wave
D	A sine wave

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Modulation index
B	FM compressibility
C	Quieting index
D	Percentage of modulation

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, redundant data is substituted
B	Special polynomial codes provide automatic correction
C	Special binary codes provide automatic correction
D	If errors are detected, a retransmission is requested

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It is possible to transmit both upper and lower case text
B	It uses one character as a shift code to send numeric and special characters
C	It contains fewer information bits per character than any other code
D	It includes built in error correction features

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

Select	Answer
A	78.7 watts
B	1977 watts
C	420 watts
D	286 watts

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	25 degrees
B	7.5 degrees
C	75 degrees
D	45 degrees

44. - E9C05

What is an OCFD antenna?

Select	Answer
A	A remotely tunable dipole antenna using orthogonally controlled frequency diversity
B	A multiband dipole antenna using one-way circular polarization for frequency diversity
C	An eight band dipole antenna using octophase filters
D	A dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation

45. - E9D04

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

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

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

47. - E9F03

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

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

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The current axis
B	The resistance axis
C	The voltage axis
D	The reactance axis

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It is electro statically balanced against ground, giving better nulls
B	It eliminates tracking errors caused by strong out-of-band signals
C	It allows stations to communicate without giving away their position
D	It automatically cancels ignition noise in mobile installations

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Advise your neighbors of the results of your tests
B	You need only evaluate exposure levels on your own property
C	Make sure signals from your station are less than the controlled MPE limits
D	Make sure signals from your station are less than the uncontrolled MPE limits

Figure E6-5

Figure E9-2

Figure E9-3