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

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	Any transmitted signal that unintentionally interferes with another licensed radio station
B	A signal transmitted to prevent its detection by any station other than the intended recipient
C	An amateur station transmission made at random without the proper call sign identification
D	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C12

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

Select	Answer
A	All of these choices are correct
B	Business-related messages for non-profit organizations
C	Communications incidental to the purpose of the amateur service and remarks of a personal nature
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 and 33 cm
D	70 cm only

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

Select	Answer
A	Record the exam session on video tape for later review by the VE team
B	Use a real-time video link and the Internet to connect the exam session to the observing VEs
C	The exam proctor observes the applicants and reports any violations
D	Have each applicant sign an affidavit stating that all session rules were followed

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must exhibit a gain of 0 dB or less over its full output range
B	It must be capable of external RF switching between its input and output networks
C	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
D	It must produce full legal output when driven by not more than 5 watts of mean RF input power

7. - E2A02

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

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

8. - E2B04

What is blanking in a video signal?

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

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To improve operating efficiency by reducing interference
B	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
C	To separate the calling stations from the DX station
D	All of these choices are correct

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To upload operational software for the transponder
B	To store digital messages in the satellite for later download by other stations
C	To relay messages between satellites
D	To delay download of telemetry between satellites

11. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	Hellschreiber
B	AMTOR
C	RTTY
D	PACTOR

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	North
B	East
C	South
D	West

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Successive ionospheric reflections without an intermediate reflection from the ground
B	Propagation away from the great circle bearing between stations
C	Signals reflected back toward the transmitting station
D	Propagation across the geomagnetic equator

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Horizontal
B	Elliptical
C	Vertical
D	Circular

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Logic analyzer
B	Bit error rate tester
C	Network analyzer
D	Modulation monitor

16. - E4B15

Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?

Select	Answer
A	The resonant frequency of the circuit
B	The bandwidth of the circuit's frequency response
C	The inductance to capacitance ratio
D	The frequency shift

17. - E4C12

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

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

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To increase rejection of unwanted signals
B	To allow selection of the optimum RF amplifier device
C	To provide a range of AGC time constants
D	To store often-used frequencies

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Reactive current only
B	Common-mode current
C	Differential-mode current
D	Return current

20. - E5A15

Which of the following can increase Q for inductors and capacitors?

Select	Answer
A	Higher self-resonant frequency
B	Lower losses
C	Lower reactance
D	Lower self-resonant frequency

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	440 seconds
B	220 seconds
C	55 seconds
D	110 seconds

22. - E5C09

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

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

23. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	To avoid unwanted inductive reactance
B	All of these choices are correct
C	To maintain component lifetime
D	To increase the thermal time constant

24. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

Select	Answer
A	Only P-type semiconductor material can conduct current
B	Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
C	Only N-type semiconductor material can conduct current
D	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Zener diode
B	Tunnel diode
C	Varactor diode
D	Silicon-controlled rectifier

26. - E6C10

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

Select	Answer
A	4
B	3
C	1
D	2

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

Select	Answer
A	Ferrite and brass
B	Polystyrene and polyethylene
C	Cobalt and aluminum
D	Teflon and Delrin

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Low leakage doubly insulated package
B	Two chips in each package (Dual In Package)
C	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
D	Package mounts in a direct inverted position

29. - E6F01

What is photoconductivity?

Select	Answer
A	The decreased conductivity of an illuminated semiconductor
B	The increased conductivity of an illuminated semiconductor
C	The conversion of electromotive energy to photon energy
D	The conversion of photon energy to electromotive energy

30. - E7A10

What is a truth table?

Select	Answer
A	A list of inputs and corresponding outputs for a digital device
B	A diagram showing logic states when the digital device output is true
C	A table of logic symbols that indicate the high logic states of an op-amp
D	A table of logic symbols that indicate the logic states of an op-amp

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 maintain the sidebands, thus causing multiple duplicate signals
C	Because they are relatively close in frequency to the desired signal
D	Because they are relatively far in frequency from the desired signal

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The relative frequencies of the individual crystals
B	The amplitude of the signals passing through the filter
C	The gain of the RF stage preceding the filter
D	The DC voltage applied to the quartz crystal

33. - E7D15

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

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

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of an amplifier tank circuit to produce AM signals
B	By varying the tuning of an amplifier tank circuit to produce PM signals
C	By varying the tuning of a microphone preamplifier to produce AM signals
D	By varying the tuning of a microphone preamplifier to produce PM signals

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 converted to a control voltage for a voltage controlled oscillator
C	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
D	A switching mixer is used to generate I and Q signals directly from the RF input

36. - E7G08

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

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

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a quartz crystal
C	Through a tapped coil
D	Through link coupling

38. - E8A02

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

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

39. - E8B02

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

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

40. - E8C01

How is Forward Error Correction implemented?

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

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 contains fewer information bits per character than any other code
C	It includes built in error correction features
D	It uses one character as a shift code to send numeric and special characters

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	6.17 dB
B	14.15 dB
C	12.5 dB
D	9.85 dB

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Radiation resistance
B	Azimuth
C	Elevation
D	Polarization

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The low-angle radiation decreases
B	The low-angle radiation increases
C	Both the high-angle and low-angle radiation decrease
D	The high-angle radiation increases

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The front-to-back ratio decreases
B	The frequency response is widened over the whole frequency band
C	The SWR is reduced
D	The front-to-back ratio increases

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. - E9F04

What is the typical velocity factor for a coaxial cable with solid polyethylene dielectric?

Select	Answer
A	0.30
B	0.10
C	2.70
D	0.66

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

Select	Answer
A	In fractions of antenna electrical wavelength
B	In fractions of transmission line electrical wavelength
C	In fractions of antenna electrical frequency
D	In fractions of transmission line electrical frequency

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A small coil of wire tightly wound around a toroidal ferrite core
B	A large circularly polarized antenna
C	A vertical antenna coupled to a feed line through an inductive loop of wire
D	One or more turns of wire wound in the shape of a large open coil

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	All of these choices are correct
B	Ground reflections and scattering make the field impedance vary with location
C	The body reacts to electromagnetic radiation from both the E and H fields
D	E field and H field radiation intensity peaks can occur at different locations

Figure E6-5

Figure E9-2