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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	60 meter band
B	17 meter band
C	30 meter band
D	12 meter band

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	30 miles
C	3 miles
D	1 mile

3. - E1C07

What is meant by local control?

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

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	All of these choices are correct
B	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
C	The space station must cease all transmissions after 5 years
D	The space station must be capable of changing its orbit whenever such a change is ordered by NASA

5. - E1E03

What is a Volunteer Examiner Coordinator?

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

6. - E1F09

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

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

7. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

Select	Answer
A	PSK and Packet
B	SSB and SSTV
C	FM and CW
D	All of these choices are correct

8. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	A special front end limiter
B	A special notch filter to remove synchronization pulses
C	No other hardware is needed
D	A special IF converter

9. - E2C05

What is the function of a DX QSL Manager?

Select	Answer
A	To allocate frequencies for DXpeditions
B	To run a net to allow many stations to contact a rare DX station
C	To relay calls to and from a DX station
D	To handle the receiving and sending of confirmation cards for a DX station

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	JT65
B	PACTOR III
C	Olivia
D	FSK441

11. - E2E06

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

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

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	West
B	North
C	South
D	East

13. - E3B09

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

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

14. - E3C11

What does VOACAP software model?

Select	Answer
A	VHF radio propagation
B	AC voltage and impedance
C	AC current and impedance
D	HF propagation

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Storage of traces for future reference
B	Automatic amplitude and frequency numerical readout
C	All of these choices are correct
D	Manipulation of time base after trace capture

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It provides an excellent match under all conditions
B	It is relatively immune to drift in the signal generator source
C	It can display results directly in Smith chart format
D	It is very precise in obtaining a signal null

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	Desensitization
D	Cross-modulation interference

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
B	The difference in dB between the noise floor and the third order intercept point
C	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
D	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor

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

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

Select	Answer
A	Reactance of either the inductance or capacitance divided by the resistance
B	Resistance divided by the reactance of either the inductance or capacitance
C	Reactance of either the inductance or capacitance multiplied by the resistance
D	Reactance of the inductance multiplied by the reactance of the capacitance

21. - E5B03

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

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

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	X
B	+jX
C	-jX
D	Omega

23. - E5D14

What is reactive power?

Select	Answer
A	Power consumed in wire resistance in an inductor
B	Power consumed in circuit Q
C	Wattless, nonproductive power
D	Power lost because of capacitor leakage

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	Bipolar
B	N-type
C	P-type
D	Insulated gate

25. - E6B04

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

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

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	Ability to connect many device outputs to a common bus
B	More efficient arithmetic operations
C	High speed operation
D	Low power consumption

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

Select	Answer
A	From about 100 kHz to at least 1000 GHz
B	From a few kHz to no more than 30 MHz
C	From approximately 10 Hz to no more than 3000 kHz
D	From less than 20 Hz to approximately 300 MHz

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Silicon
B	Silicon nitride
C	Gallium nitride
D	Silicon dioxide

29. - E6F07

What is a solid state relay?

Select	Answer
A	A relay using transistors to drive the relay coil
B	A passive delay line
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A mechanical relay that latches in the on or off state each time it is pulsed

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	An XOR gate
B	A multiplexer
C	A flip-flop
D	An OR gate

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Increased overall intelligibility
B	Signal inversion
C	Reduced intermodulation products
D	Signal distortion and excessive bandwidth

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	Pi-networks are designed for balanced input and output
B	Pi-networks have fewer components
C	The Q of Pi-networks can be varied depending on the component values chosen
D	L-networks cannot perform impedance transformation

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Output voltage multiplied by output current
B	Input voltage multiplied by input current
C	Input voltage divided by output current
D	Voltage difference from input to output multiplied by output current

34. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the audio amplifier
B	A reactance modulator on the oscillator
C	A balanced modulator on the oscillator
D	A reactance modulator on the final amplifier

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	Complex phasor representations
B	More taps
C	Higher data rate
D	Double-precision math routines

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	An echo caused by a long time delay
B	Undesired oscillations added to the desired signal
C	A reduction in high frequency response
D	Partial cancellation of the signal over a range of frequencies

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
B	An electronic circuit also known as a monostable multivibrator
C	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
D	An electronic circuit consisting of a precision push-pull amplifier with a differential input

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	All of these choices are correct
C	Digital signals always occupy a narrower bandwidth
D	Digital signals can be regenerated multiple times without error

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	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
D	The transmitted signal jumps from band to band at a predetermined rate

40. - E8C09

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

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to change frequencies
B	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	The receiver is always equipped with a digital blanker

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	3.85 dB
B	8.15 dB
C	6.0 dB
D	2.79 dB

43. - E9B09

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

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

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It reduces losses in the radiating portion of the antenna
B	It reduces low-angle radiation
C	It causes increased SWR
D	It changes the impedance angle of the matching network

45. - E9D13

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

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

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

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	A capacitive reactance
C	The same as the input impedance to the final generator stage
D	An inductive reactance

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. - E9H04

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

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

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Beryllium Oxide
B	Uranium Hexafluoride
C	Mica
D	Zinc oxide