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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	2.8 kHz
B	170 Hz
C	60 Hz
D	1.5 kHz

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C07

What is meant by local control?

Select	Answer
A	Controlling a station through a local auxiliary link
B	Direct manipulation of the transmitter by a control operator
C	Controlling a repeater using a portable handheld transceiver
D	Automatically manipulating local station controls

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
B	Any amateur station designated by NASA
C	All of these choices are correct
D	Any amateur station so designated by the ITU

5. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Immediately terminate everyone's examination and close the session
B	Immediately terminate the candidate's examination
C	Warn the candidate that continued failure to comply will result in termination of the examination
D	Allow the candidate to complete the examination, but invalidate the results

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 W
B	1.5 kW
C	1 W
D	10 W

7. - E2A09

What do the terms L band and S band specify with regard to satellite communications?

Select	Answer
A	FM and Digital Store-and-Forward systems
B	The 2 meter and 70 centimeter bands
C	The 23 centimeter and 13 centimeter bands
D	Which sideband to use

8. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

Select	Answer
A	By scanning lines from left to right in one field and right to left in the next
B	By scanning two fields simultaneously
C	By scanning each field from bottom to top
D	By scanning odd numbered lines in one field and even numbered lines in the next

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	30 m
B	6 m
C	33 cm
D	2 m

10. - E2D04

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

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

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK uses a DC-coupled data connection
B	Audio FSK can be performed anywhere in the transmit chain
C	Audio FSK has a superior frequency response
D	Direct FSK applies the data signal to the transmitter VFO

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Temperature inversion
B	Wind shear
C	The jet stream
D	Dust devil

13. - E3B09

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

Select	Answer
A	Around the solstices, especially the summer solstice
B	Around the equinoxes, especially the fall equinox
C	Around the equinoxes, especially the spring equinox
D	Around the solstices, especially the winter solstice

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	10 percent greater
B	Twice as great
C	Four times as great
D	50 percent greater

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

Select	Answer
A	It can run on battery power for remote measurements
B	It provides improved resolution of low-frequency signals within a comparable time period
C	It does not require an expensive high-precision time base
D	It can directly measure the modulation index of an FM transmitter

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	146.52 kHz
B	1465.20 Hz
C	146.52 Hz
D	10 Hz

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Capture effect
B	Frequency discrimination
C	Cross-modulation interference
D	Desensitization

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	A reduction in apparent signal strength
B	A large increase in background noise
C	The off-frequency unwanted signal is heard in addition to the desired signal
D	The desired signal can no longer be heard

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Common mode currents on the shield and conductors
B	Tying all ground connections to a common point resulting in differential mode currents in the shield
C	Low inductance ground connections at both ends of the shield
D	Use of braided shielding material

20. - E5A15

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

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

21. - E5B03

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

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

22. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

Select	Answer
A	Maidenhead grid
B	Elliptical coordinates
C	Faraday grid
D	Polar coordinates

23. - E5D15

What is the power factor of an R-L circuit having a 45 degree phase angle between the voltage and the current?

Select	Answer
A	0.5
B	1.0
C	0.866
D	0.707

24. - E6A03

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

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

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Junction
B	Zener
C	Point contact
D	Tunnel

26. - E6C05

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

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

27. - E6D03

Which of the following is an aspect of the piezoelectric effect?

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

28. - E6E11

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

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

29. - E6F10

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

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

30. - E7A01

Which is a bi-stable circuit?

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

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	Low bandwidth
B	High filament voltage
C	High power gain
D	Low input impedance

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. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
B	It uses a diode bridge rectifier for increased output
C	It uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle
D	The inverter design does not require any output filtering

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

Select	Answer
A	An FM generator circuit
B	A circuit for detecting FM signals
C	A circuit for filtering two closely adjacent signals
D	An automatic band-switching circuit

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	An adaptive filter
B	A Hilbert-transform filter
C	A notch filter
D	An elliptical filter

36. - E7G08

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

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

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

38. - E8A09

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

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

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Percentage of modulation
B	Quieting index
C	FM compressibility
D	Modulation index

40. - E8C05

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

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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Bit errors in the modem
B	Excessive transmit audio levels
C	Excessive numbers of retries
D	Ground loops

42. - E9A08

What is meant by antenna bandwidth?

Select	Answer
A	Antenna length divided by the number of elements
B	The frequency range over which an antenna satisfies a performance requirement
C	The angle formed between two imaginary lines drawn through the element ends
D	The angle between the half-power radiation points

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Graphical analysis
B	Method of Moments
C	Mutual impedance analysis
D	Calculus differentiation with respect to physical properties

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

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

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	As close to the transmitter as possible
B	As low as possible on the vertical radiator
C	At a voltage node
D	Near the center of 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 radiation resistance must be higher than the characteristic impedance of the transmission line
B	The driven element resonance must be lower than the operating frequency
C	The driven element reactance must be capacitive
D	The driven element reactance must be inductive

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	2.3 meters
B	20 meters
C	3.5 meters
D	0.2 meters

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning impedance values with regard to the prime center
B	Reassigning resistance values with regard to the reactance axis
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning prime center with regard to the reactance axis

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	Atmospheric noise is so high that gain over a dipole is not important
B	All of these choices are correct
C	They must be erected at least 1/2 wavelength above the ground to attain good directivity
D	Low loss coax transmission line is essential for good performance

50. - E0A10

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

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