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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the center frequency of the channel
B	At the highest frequency of the channel
C	At the lowest frequency of the channel
D	On any frequency where the signal's sidebands are within the channel

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	0.5
B	3.0
C	2.0
D	1.0

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	5 minutes
B	3 minutes
C	30 seconds
D	10 minutes

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A radio communications service using amateur radio stations on satellites
B	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
C	A radio communications service using stations on Earth satellites for public service broadcast
D	A spacecraft launching service for amateur-built satellites

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	5
B	3
C	2
D	4

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide for experimental amateur communications
B	To provide additional spectrum for personal use
C	To provide temporary operation while awaiting normal licensing
D	To allow regular operation on Land Mobile channels

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The uplink and downlink frequency ranges
B	The polarization of uplink and downlink signals
C	The location of the ground control station
D	Power limits for uplink and downlink transmissions

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Specific tone frequencies
B	Elapsed time
C	A two-tone signal
D	Specific tone amplitudes

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

10. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	802.11
B	AMTOR
C	PACTOR
D	AX.25

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Forward Error Correction
B	Fatal Error Correction
C	First Error Correction
D	Final Error Correction

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	The waves are reflected by the ionosphere and return to their source
B	The energy propagates through a medium with a high refractive index
C	Changing electric and magnetic fields propagate the energy
D	Electric and magnetic fields become aligned as they travel

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Any time
B	Around sunrise
C	Around sunset
D	Early evening

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Sporadic-E
B	NVIS
C	Transequatorial propagation
D	Polar paths

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and time
B	SWR and time
C	SWR and frequency
D	RF amplitude and frequency

16. - E4B08

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

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

17. - E4C07

What does the MDS of a receiver represent?

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

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
B	Oscillator instability and severe audio distortion of all but the strongest received signals
C	Cross-modulation of the desired signal and desensitization from strong adjacent signals
D	Cross-modulation of the desired signal and insufficient audio power to operate the speaker

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By checking the power line voltage with a time domain reflectometer
B	By observing the AC power line voltage with a spectrum analyzer
C	By observing the AC power line waveform with an oscilloscope
D	By turning off the AC power line main circuit breaker and listening on a battery operated radio

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	23.67 kHz
B	157.8 Hz
C	315.6 Hz
D	47.3 kHz

21. - E5B05

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

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

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By Y and G values
B	By X and R values
C	By phase angle and amplitude
D	By real and imaginary parts

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Malleability
B	Inductance
C	Permittivity
D	Permeability

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	They are both high impedance
B	They are both low impedance
C	An FET has low input impedance; a bipolar transistor has high input impedance
D	An FET has high input impedance; a bipolar transistor has low input impedance

25. - E6B05

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

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

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Lower distortion
B	Differential output capability
C	Lower power consumption
D	Immune to damage from static discharge

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	Harmonics and distortion could result
B	Temporary changes of the core permeability could result
C	Magnetic flux would increase with frequency
D	RF susceptance would increase

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	TO-220
B	Surface mount
C	Radial lead
D	Axial lead

29. - E6F14

Which of the following is true of LCD displays?

Select	Answer
A	They may be hard view through polarized lenses
B	They are hard to view in high ambient light conditions
C	All of these choices are correct
D	They only display alphanumeric symbols

30. - E7A01

Which is a bi-stable circuit?

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

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Fixed bias
B	Emitter bypass
C	Output load resistor
D	Self bias

32. - E7C04

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

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

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	The resistance of a control element is varied in direct proportion to the line voltage or load current
B	It is generally less efficient than a linear regulator
C	It gives a ramp voltage at its output
D	The controlled device's duty cycle is changed to produce a constant average output voltage

34. - E7E04

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

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

35. - E7F07

What function can a Fast Fourier Transform perform?

Select	Answer
A	Converting digital signals from the time domain to the frequency domain
B	Converting 8-bit data to 16 bit data
C	Converting analog signals to digital form
D	Converting digital signals to analog form

36. - E7G12

What is an integrated circuit operational amplifier?

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

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 hybrid synthesizer
C	A phase locked loop synthesizer
D	A diode-switching matrix synthesizer

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Harmonic regeneration
B	Level shifting
C	Sequential sampling
D	Phase reversal

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It increases as the RF carrier frequency increases
B	It varies with the square root of the RF carrier frequency
C	It decreases as the RF carrier frequency increases
D	It does not depend on the RF carrier frequency

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	4.8 kHz
B	9.6 kHz
C	15.36 kHz
D	5.76 kHz

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	Foreign language characters can be sent
B	Faster transmission rate
C	The signal can overpower interfering signals
D	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth

42. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

Select	Answer
A	Sunspot activity and time of day
B	Transmission-line length
C	The settings of an antenna tuner at the transmitter
D	Antenna height, conductor length/diameter ratio and location of nearby conductive objects

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

Select	Answer
A	Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference
B	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
C	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
D	Draw two imaginary lines through the ends of the elements and measure the angle between the lines

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	A dipole constructed from zip cord
B	An end fed dipole antenna
C	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
D	An omni-directional antenna commonly used for satellite communications

45. - E9D01

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

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

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	An SWR less than 1:1
B	A reflection coefficient greater than 1
C	An SWR greater than 1:1
D	A dielectric constant greater than 1

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	50 meters
B	6.9 meters
C	24 meters
D	10 meters

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radiation resistance
B	Antenna radiation pattern
C	Radio propagation
D	Impedance along transmission lines

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
B	It narrows the bandwidth of the received signal to improve signal to noise ratio
C	It prevents receiver overload which could make it difficult to determine peaks or nulls
D	It compensates for the effects of an isotropic antenna, thereby improving directivity

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	Polyethylene
C	Polymorphic silicon
D	Polytetrafluroethylene

Figure E7-1