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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	1 kHz above the lower band edge
B	3 kHz above the lower band edge
C	The exact lower band edge
D	300 Hz above the lower band edge

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Only those club stations licensed to Amateur Extra class operators
B	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
C	Any FCC-licensed amateur station except a Technician class
D	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	The use of a control link between a control point and a locally controlled station
B	Remotely controlling a station's antenna pattern through a directional control link
C	A station operating with its output power controlled automatically
D	The use of devices and procedures for control so that the control operator does not have to be present at a control point

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 is not able to communicate using amateur satellites
C	Any amateur station on the surface of the Earth
D	An amateur station that transmits telemetry consisting of measurement of upper atmosphere

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Return the application document to the examinee
B	Destroy the application form
C	Maintain the application form with the VEC's records
D	Send the application form to the FCC and inform the FCC of the grade

6. - E1F04

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

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

7. - E2A10

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

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

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 while it is traveling from right to left or from bottom to top
C	Turning off the scanning beam at the conclusion of a transmission
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	33 cm
B	6 m
C	30 m
D	2 m

10. - E2D11

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

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

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	170 Hz shift, 45 baud RTTY
B	300-baud packet
C	PSK31
D	MFSK16

12. - E3A14

From the contiguous 48 states, in which approximate direction should an antenna be pointed to take maximum advantage of aurora propagation?

Select	Answer
A	East
B	South
C	West
D	North

13. - E3B06

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

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

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. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

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

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High reluctance input
B	Low reluctance input
C	Low impedance input
D	High impedance input

17. - E4C12

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?

Select	Answer
A	Output-offset overshoot
B	Filter ringing
C	Undesired signals may be heard
D	Thermal-noise distortion

18. - E4D13

Which of the following can cause receiver desensitization?

Select	Answer
A	Audio bias adjusted too high
B	Squelch gain misadjusted
C	Audio gain adjusted too low
D	Strong adjacent channel signals

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

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	Matching bandwidth is decreased
B	It has no effect on impedance matching
C	Matching bandwidth is increased
D	Matching range is increased

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	X
B	G
C	B
D	Y

22. - E5C06

What does the impedance 50-j25 represent?

Select	Answer
A	50 ohms resistance in series with 25 ohms capacitive reactance
B	50 ohms resistance in series with 25 ohms inductive reactance
C	25 ohms resistance in series with 50 ohms capacitive reactance
D	25 ohms resistance in series with 50 ohms inductive reactance

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.5
C	1.414
D	1.73

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	1
B	6
C	3
D	2

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a high voltage rectifier
B	As a constant current source
C	As an RF detector
D	As a constant voltage source

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor connected to an op-amp output that only functions when the logic output is false
B	A resistor in a keying circuit used to reduce key clicks
C	A resistor that insures that an oscillator frequency does not drive lower over time
D	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

27. - E6D08

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

Select	Answer
A	Powdered-iron cores generally require fewer turns to produce a given 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 use smaller diameter wire for the same inductance

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It is used in a battery charger circuit
B	It is a CMOS analog-to-digital converter
C	Its phase shift changes rapidly with frequency
D	It samples an analog signal and passes it in stages from the input to the output

29. - E6F10

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

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

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	J-K flip-flop
C	Monostable multivibrator
D	T flip-flop

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

Select	Answer
A	Class AB
B	Push-push
C	Push-pull
D	Class C

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Gradual passband rolloff with minimal stop band ripple
B	Gradual passband rolloff with extreme stop band ripple
C	Extremely sharp cutoff with one or more notches in the stop band
D	Extremely flat response over its pass band with gradually rounded stop band corners

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A shunt regulator
B	A series current source
C	A shunt current source
D	A series regulator

34. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A reactance modulator on the oscillator
B	A reactance modulator on the final amplifier
C	A balanced modulator on the oscillator
D	A balanced modulator on the audio amplifier

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Change the gain by a factor of 3/4
B	Add 3 to each input value and subtract 4 from each output value
C	Multiply each sample value by a factor of 3/4
D	Interpolate by a factor of three, then decimate by a factor of four

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A RF amplifier used in the UHF and microwave regions
B	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
C	A digital audio amplifier whose characteristics are determined by components external to the amplifier
D	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance

37. - E7H10

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

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

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	Fourier analysis
C	Vector analysis
D	Differential analysis

39. - E8B11

What is digital time division multiplexing?

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

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

Select	Answer
A	All of these choices are correct
B	This results in the least possible transmitted bandwidth for the particular mode
C	It is easier to demodulate with a conventional, non-synchronous detector
D	It improves carrier suppression

41. - E8D06

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

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

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Shorten the radiating element
B	Install a good radial system
C	Reduce the diameter of the radiating element
D	Isolate the coax shield from ground

43. - E9B06

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

Select	Answer
A	7.5 degrees
B	25 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 dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
C	An eight band dipole antenna using octophase filters
D	A multiband dipole antenna using one-way circular polarization for frequency diversity

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	Near the center of the vertical radiator
D	As low as possible on the vertical radiator

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

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

Select	Answer
A	The center conductor resistivity
B	The line length
C	The termination impedance
D	Dielectric materials used in the line

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Standing wave ratio circles
B	Radiation-pattern circles
C	Coaxial-length circles
D	Antenna-length circles

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 automatically cancels ignition noise in mobile installations
C	It eliminates tracking errors caused by strong out-of-band signals
D	It allows stations to communicate without giving away their position

50. - E0A07

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

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

Figure E6-2

Figure E9-2