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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

Select	Answer
A	Any FCC-issued amateur license
B	Only General class or higher amateur licenses
C	An unrestricted Radiotelephone Operator Permit
D	Any amateur license with an FCC Marine or Aircraft endorsement

2. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must cease operation on all frequencies below 30 MHz
B	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference
C	The amateur station must cease operation
D	The amateur station must cease operation on all frequencies above 30 MHz

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	Communications incidental to the purpose of the amateur service and remarks of a personal nature
C	Messages intended for connection to users of the maritime satellite service
D	Business-related messages for non-profit organizations

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

Select	Answer
A	Only Amateur Extra Class
B	Only General, Advanced or Amateur Extra Class
C	All except Technician Class
D	Any class with appropriate operator privileges

5. - E1E01

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

Select	Answer
A	4
B	5
C	3
D	2

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
B	All of these choices are correct
C	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
D	The transmission must not be used to obscure the meaning of any communication

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	An isotropic antenna
B	A log-periodic dipole array
C	A linearly polarized antenna
D	A circularly polarized antenna

8. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To provide vertical synchronization
B	To identify the SSTV mode being used
C	To lock the color burst oscillator in color SSTV images
D	To identify the call sign of the station transmitting

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Contacts between a U.S. station and a non-U.S. station
B	Repeater contacts between U.S. club members
C	Special event contacts between stations in the U.S.
D	Contacts using tactical call signs

10. - E2D11

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

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

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PSK31
B	MT63
C	RTTY
D	PACTOR

12. - E3A15

What is an electromagnetic wave?

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

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	The signal experiences less loss along the path compared to normal skip propagation
B	Atmospheric noise is lower in the direction of chordal hop propagation
C	Signals travel faster along ionospheric chords
D	The MUF for chordal hop propagation is much lower than for normal skip propagation

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class A
B	Class X
C	Class B
D	Class M

15. - E4A02

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

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

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	A less accurate reading results
B	Cross modulation occurs
C	Intermodulation distortion occurs
D	Harmonics are generated

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

Select	Answer
A	13.845 MHz
B	15.210 MHz
C	14.445 MHz
D	14.755 MHz

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Increase the receiver front end gain
B	Decrease the RF bandwidth of the receiver
C	Switch from fast AGC to slow AGC
D	Raise the receiver IF frequency

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

Select	Answer
A	A DSP filter can remove the desired signal at the same time as it removes interfering signals
B	Ringing in the DSP filter will completely remove the spaces between the CW characters
C	Received CW signals will appear to be modulated at the DSP clock frequency
D	Any nearby signal passing through the DSP system will overwhelm the desired signal

20. - E5A17

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

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

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Current leads voltage by 90 degrees
B	Voltage leads current by 90 degrees
C	Voltage and current are 180 degrees out of phase
D	Voltage and current are in phase

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	Resistive component
C	The difference between the resistive and reactive components
D	Reactive component

23. - E5D01

What is the result of skin effect?

Select	Answer
A	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
B	Thermal effects on the surface of the conductor increase the impedance
C	Thermal effects on the surface of the conductor decrease the impedance
D	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface

24. - E6A11

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

Select	Answer
A	6
B	2
C	3
D	1

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	5
B	1
C	6
D	7

26. - E6C10

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

Select	Answer
A	1
B	4
C	3
D	2

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 use smaller diameter wire for the same inductance
C	Powdered-iron cores generally have greater initial permeability
D	Powdered-iron cores generally maintain their characteristics at higher currents

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Stripped lead
B	Surface mount
C	Virtual lead mounting
D	Direct soldering

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	A liquid semiconductor
B	A crystalline semiconductor
C	A heavy metal
D	An ordinary metal

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. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	At a point where the load line intersects the zero bias current curve
B	At a point where the bias resistor equals the load resistor
C	Where the load line intersects the voltage axis
D	Approximately half-way between saturation and cutoff

32. - E7C04

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

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

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Control of electrolyte levels during battery discharge
B	Prevention of battery damage due to overcharge
C	Prevention of battery undercharge
D	Matching of day and night charge rates

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	Spurious mixer products are generated
B	A beat frequency is generated
C	Mixer blanking occurs
D	Automatic limiting occurs

35. - E7F03

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

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

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	47
B	24
C	0.21
D	94

37. - E7H02

Which describes a microphonic?

Select	Answer
A	Distortion caused by RF pickup on the microphone cable
B	Excess loading of the microphone by an oscillator
C	Changes in oscillator frequency due to mechanical vibration
D	An IC used for amplifying microphone signals

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	100 to 1
B	2.5 to 1
C	1 to 1
D	25 to 1

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	Two or more information streams are merged into a baseband, which then modulates the transmitter
C	The transmitted signal jumps from band to band at a predetermined rate
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Excess 3 code
C	Extended Binary Coded Decimal Interchange Code
D	Gray code

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

Select	Answer
A	+10 dB
B	-20 dB
C	+15 dB
D	-30 dB

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Radiation resistance plus space impedance
B	Radiation resistance plus transmission resistance
C	Transmission-line resistance plus radiation resistance
D	Radiation resistance plus ohmic resistance

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

Select	Answer
A	The total amount of radiation from the directional antenna is increased by the gain of the antenna
B	They are the same
C	The total amount of radiation from the directional antenna is stronger by its front-to-back ratio
D	The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna

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

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	A single 12 gauge or 10 gauge stainless steel wire
B	A cable with six or seven 18 gauge conductors in parallel
C	A wide flat copper strap
D	A resistive wire, such as spark plug wire

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Connect a series-resonant LC network across the antenna feed terminals
B	Use the universal stub matching technique
C	Connect a parallel-resonant LC network across the antenna feed terminals
D	Use a 50 ohm 1:1 balun between the antenna and feed line

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	Very low impedance
B	The same as the characteristic impedance of the line
C	The same as the output impedance of the generator
D	Very high impedance

48. - E9G01

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

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

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	Antenna headings from several different receiving locations are used to locate the signal source
B	A fixed receiving station uses three different antennas to plot the location of the signal source
C	The geometric angles of sky waves from the source are used to determine its position
D	A fixed receiving station plots three headings to the signal source

50. - E0A08

What does SAR measure?

Select	Answer
A	The rate of RF energy reflected from stationary terrain
B	The rate at which RF energy is absorbed by the body
C	Signal Amplification Rating
D	Synthetic Aperture Ratio of the human body

Figure E6-2

Figure E6-3

Figure E6-5

Figure E7-4