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

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	3 miles
C	1 mile
D	30 miles

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

Select	Answer
A	A control operator need not be present at the control point
B	Only Extra Class operators may be the control operator of a remote station
C	A control operator must be present at the control point
D	Repeater and auxiliary stations may not be remotely controlled

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	6 meters, 2 meters, and 1.25 meters
B	6 meters and 2 meters
C	2 meters
D	2 meters and 1.25 meters

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

6. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When transmitting international third-party communications
B	When neither the amateur nor his or her employer has a pecuniary interest in the communications
C	When the control operator is employed by the FCC or another government agency
D	When the total money involved does not exceed $25

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From south to north
B	From north to south
C	From west to east
D	From east to west

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 provide vertical synchronization
C	To identify the SSTV mode being used
D	To identify the call sign of the station transmitting

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A method of exchanging information during a contest QSO
B	The rules of order for meetings between contest sponsors
C	The most common set of contest rules
D	A standard for submission of electronic contest logs

10. - E2D13

What type of modulation is used for JT65 contacts?

Select	Answer
A	PSK
B	IEEE 802.11
C	Multi-tone AFSK
D	RTTY

11. - E2E12

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

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

12. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

Select	Answer
A	500 miles, if the Moon is at perigee
B	12,000 miles, if the Moon is visible by both stations
C	2000 miles, if the Moon is at apogee
D	5000 miles, if the Moon is at perigee

13. - E3B10

What is the cause of gray-line propagation?

Select	Answer
A	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves
B	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
C	At twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high
D	In darkness, solar absorption drops greatly while atmospheric ionization remains steady

14. - E3C07

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

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

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	A Q meter
B	A spectrum analyzer
C	An ohmmeter
D	An antenna analyzer

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

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	One-half the maximum sampling buffer size
B	The reference voltage of the analog-to-digital converter
C	The maximum count value of the analog-to-digital converter
D	One-half the maximum sample rate

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	146.10 MHz and 147.30 MHz
B	146.34 MHz and 146.61 MHz
C	146.88 MHz and 146.34 MHz
D	173.35 MHz and 139.40 MHz

19. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals which are constant at all IF levels
B	Signals which appear at one IF but not another
C	Signals which have a sharply peaked frequency distribution
D	Signals which appear across a wide bandwidth

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

Select	Answer
A	Resistance
B	Capacitance
C	Resonance
D	Conductance

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	One discharge period
B	An exponential discharge rate of one
C	A discharge factor of one
D	One time constant

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A negative real part
B	A positive real part
C	A negative phase angle
D	A positive phase angle

23. - E5D04

Why are short connections necessary at microwave frequencies?

Select	Answer
A	To reduce phase shift along the connection
B	Because of ground reflections
C	To reduce noise figure
D	To increase neutralizing resistance

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To keep the gate voltage within specifications and prevent the device from overheating
B	To provide a voltage reference for the correct amount of reverse-bias gate voltage
C	To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
D	To protect the substrate from excessive voltages

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Reverse bias controls its forward voltage drop
B	Extremely high reverse breakdown voltage
C	A large region of intrinsic material
D	Ability to dissipate large amounts of power

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

Select	Answer
A	2
B	1
C	4
D	3

27. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Select	Answer
A	Powdered-iron cores use smaller diameter wire for the same inductance
B	Powdered-iron cores generally have greater initial permeability
C	Powdered-iron cores generally maintain their characteristics at higher currents
D	Powdered-iron cores generally require fewer turns to produce a given inductance

28. - E6E02

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

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

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A display that uses a glowing liquid to remain brightly lit in dim light
B	A frequency-determining unit for a transmitter or receiver
C	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
D	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Astable multivibrator
B	T flip-flop
C	Monostable multivibrator
D	J-K flip-flop

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A low-pass filter to remove switching signal components
B	A matched load resistor to prevent damage by switching transients
C	A temperature compensating load resistor to improve linearity
D	A high-pass filter to compensate for low gain at low frequencies

32. - E7C07

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

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

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	An SCR
B	A Zener diode
C	A tunnel diode
D	A varactor diode

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce PM signals by using an electrically variable resistance
B	To produce PM signals by using an electrically variable inductance or capacitance
C	To produce AM signals by using an electrically variable inductance or capacitance
D	To produce AM signals by using an electrically variable resistance

35. - E7F01

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

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

36. - E7G01

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

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

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Provide the crystal with a specified parallel inductance
B	Bias the crystal at a specified current
C	Provide the crystal with a specified parallel capacitance
D	Bias the crystal at a specified voltage

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

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

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the carrier center frequency to the audio modulating frequency
B	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
C	The ratio of the audio modulating frequency to the center carrier frequency
D	The ratio of the highest audio modulating frequency to the average audio modulating frequency

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By the receiving station repeating each block of three data characters
B	By varying the frequency shift of the transmitted signal according to a predefined algorithm
C	By transmitting a special algorithm to the receiving station along with the data characters
D	By transmitting extra data that may be used to detect and correct transmission errors

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	The generation of RF harmonics
B	Limits data speed
C	More difficult to copy
D	The generation of key clicks

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Half-wave dipole
B	Isotropic antenna
C	Yagi
D	Quarter-wave vertical

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

44. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The lobes become more perpendicular to the wire
B	The lobes align more in the direction of the wire
C	The vertical angle increases
D	The front-to-back ratio decreases

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Greater structural strength
B	Improved radiation efficiency
C	Higher losses
D	Lower Q

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It makes sure the antenna has a low-angle radiation pattern
B	It allows single-band antennas to operate on other bands
C	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
D	It ensures that each driven element operates in concert with the others to create the desired antenna pattern

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

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

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and voltage
B	Resistance and reactance
C	Reactance and voltage
D	Voltage and impedance

49. - E9H04

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

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

50. - E0A10

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

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

Figure E6-5