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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Notify the nearest FCC Field Engineer's office
B	Discontinue forwarding all messages
C	Notify the originating station that the communication does not comply with FCC rules
D	Discontinue forwarding the communication as soon as you become aware of it

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Puerto Rico surrounding the Arecibo Radio Telescope
B	An area in Florida surrounding Cape Canaveral
C	An area surrounding the National Radio Astronomy Observatory
D	An area in New Mexico surrounding the White Sands Test Area

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	All of these choices are correct
C	Business-related messages for non-profit organizations
D	Messages intended for connection to users of the maritime satellite service

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	33 cm and 13 cm
B	70 cm and 13 cm
C	70 cm only
D	70 cm and 33 cm

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	The person who has entered into an agreement with the FCC to be the VE session manager
B	A person who has volunteered to administer amateur operator license examinations
C	A person who has volunteered to prepare amateur operator license examinations
D	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations

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

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Doppler shift of beacon signals
B	Bandwidth compressed LORAN
C	Radar
D	APRS

8. - E2B14

What aspect of an amateur slow-scan television signal encodes the brightness of the picture?

Select	Answer
A	Sync amplitude
B	Sync frequency
C	Tone frequency
D	Tone amplitude

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
B	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
C	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
D	The acceptable practice of manually posting the call signs of stations on a spotting network

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	Time synchronous transmissions alternately from each station
B	High speed CW identification to avoid fading
C	Storing and forwarding digital messages
D	Judging optimum transmission times by monitoring beacons reflected from the Moon

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	110 baud
B	1200 baud
C	48 baud
D	300 baud

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
B	A wave consisting of two magnetic fields at right angles to each other
C	A wave consisting of two electric fields at parallel right angles to each other
D	A wave of alternating current, in the core of an electromagnet

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between any two points located on the magnetic equator
B	Propagation between two stations at the same latitude
C	Propagation between two continents by way of ducts along the magnetic equator
D	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It peaks at roughly 14 MHz
B	It stays the same
C	It decreases
D	It increases

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Q of the interface of the interface circuit
B	Amount of memory on the soundcard
C	Analog-to-digital conversion speed of the soundcard
D	All of these choices are correct

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

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The minimum discernible signal
B	The multiplex distortion stability
C	The maximum detectable spectrum
D	The meter display sensitivity

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
B	When the signals from the transmitters are reflected in phase from airplanes passing overhead
C	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
D	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters

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

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	15.7 kHz
B	31.4 kHz
C	218.3 kHz
D	436.6 kHz

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	One time constant
C	A discharge factor of one
D	An exponential discharge rate of one

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	The sum of the reactive and resistive components
B	The difference between the resistive and reactive components
C	Reactive component
D	Resistive component

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By dividing the reactive power by the power factor
B	By multiplying the reactive power times the power factor
C	By multiplying the apparent power times the power factor
D	By dividing the apparent power by the power factor

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free electrons
B	Holes
C	Free neutrons
D	Free protons

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To increase the sensitivity
B	To allow the comparator to be used with AC input signal
C	To cause the output to change states continually
D	To prevent input noise from causing unstable output signals

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

28. - E6E08

How is voltage from a power supply normally furnished to the most common type of monolithic microwave integrated circuit (MMIC)?

Select	Answer
A	MMICs require no operating bias
B	Directly to the bias voltage (VCC IN) lead
C	Through a resistor and/or RF choke connected to the amplifier output lead
D	Through a capacitor and RF choke connected to the amplifier input lead

29. - E6F13

What is a liquid crystal display (LCD)?

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

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic "1" at its output if all inputs are logic "0"
B	It produces logic "0" at its output if all inputs are logic "1"
C	It only produces logic "0" at its output when all inputs are logic "1"
D	It produces logic "1" at its output if any or all inputs are logic "1"

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
B	Switching amplifiers operate at higher voltages
C	Linear amplifiers have high gain resulting in higher harmonic content
D	Switching amplifiers use push-pull circuits

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It cancels the reactive part of the impedance and changes the resistive part to a desired value
B	It introduces negative resistance to cancel the resistive part of impedance
C	Network resistances are substituted for load resistances and reactances are matched to the resistances
D	It introduces transconductance to cancel the reactive part of impedance

33. - E7D11

What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?

Select	Answer
A	Switching inductance
B	Error amplifier
C	Reference voltage
D	Pass transistor

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of an amplifier tank circuit to produce PM signals
B	By varying the tuning of a microphone preamplifier to produce PM signals
C	By varying the tuning of an amplifier tank circuit to produce AM signals
D	By varying the tuning of a microphone preamplifier to produce AM 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 width in bits
B	Sample rate
C	Sample clock phase noise
D	Processor latency

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It increases linearly with increasing frequency
B	It does not vary with frequency
C	It decreases logarithmically with increasing frequency
D	It decreases linearly with increasing frequency

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Mechanically isolating the oscillator circuitry from its enclosure
B	Using the oscillator only for CW and digital signals
C	Eliminating noise on the oscillator's power supply
D	Use of NP0 capacitors

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	256 divided by the gain of the input amplifier
B	256
C	8 multiplied by the gain of the input amplifier
D	8

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A bandwidth compression technique using Fourier transforms
B	A digital mode for narrow band, slow speed transmissions
C	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
D	A frequency modulation technique which uses non-harmonically related frequencies

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 52 Hz
B	Approximately 104 Hz
C	Approximately 13 Hz
D	Approximately 26 Hz

41. - E8D11

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

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

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(radiation resistance / transmission resistance) x 100 per cent
B	(radiation resistance / total resistance) x 100 per cent
C	(total resistance / radiation resistance) x 100 per cent
D	(effective radiated power / transmitter output) x 100 percent

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	Numeric Electrical Computation
B	National Electrical Code
C	Numerical Electromagnetic Code
D	Next Element Comparison

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
B	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
C	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
D	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	A series capacitor
B	A shunt inductor
C	Pi-network
D	Pi-L-network

47. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
B	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
C	The index of shielding for coaxial cable
D	The ratio of the characteristic impedance of the line to the terminating impedance

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Free space radiation directivity chart
B	Azimuth angle radiation pattern chart
C	Elevation angle radiation pattern chart
D	Smith chart

49. - E9H04

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

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

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Only the most powerful transmitter
B	Each transmitter operating with a duty-cycle greater than 50 percent
C	Only commercial transmitters
D	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations

Figure E9-3