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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Discontinue forwarding the communication as soon as you become aware of it
B	Notify the nearest FCC Field Engineer's office
C	Notify the originating station that the communication does not comply with FCC rules
D	Discontinue forwarding all messages

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

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control the control operator is not required to be present at the control point
B	Under local control a control operator is not required to be present at a control point
C	Under automatic control there is no control operator
D	Under local control there is no control operator

4. - E1D06

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

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

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Return the application document to the examinee
B	Maintain the application form with the VEC's records
C	Send the application form to the FCC and inform the FCC of the grade
D	Destroy the application form

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 222 MHz
B	Only on amateur frequencies above 144 MHz
C	Only on amateur frequencies above 420 MHz
D	Only on amateur frequencies above 50 MHz

7. - E2A02

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

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

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Luminance
B	Hue
C	Chroma
D	Spectral Intensity

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send your full call sign once or twice
B	Send the call sign of the DX station three times, the words "this is", then your call sign three times
C	Send your full call sign and grid square
D	Send only the last two letters of your call sign until you make contact

10. - E2D11

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

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

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	MFSK
B	RTTY
C	Winlink
D	PSK31

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A slow change in the pitch of the CW signal
B	The returning echo is several Hertz lower in frequency than the transmitted signal
C	A fluttery irregular fading
D	A gradual loss of signal as the Sun rises

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

Select	Answer
A	Refracted rays and reflected waves
B	Long path and short path waves
C	Independent waves created in the ionosphere that are elliptically polarized
D	Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It increases
B	It stays the same
C	It decreases
D	It peaks at roughly 14 MHz

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	Never use a high impedance probe to measure a low impedance circuit
B	All of these choices are correct
C	Keep the signal ground connection of the probe as short as possible
D	Never use a DC-coupled probe to measure an AC circuit

16. - E4B14

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

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

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	1 kHz
B	4.8 kHz
C	2.4 kHz
D	4.2 kHz

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A properly terminated circulator at the output of the transmitter
B	A band-pass filter in the feed line between the transmitter and receiver
C	A Class D final amplifier
D	A Class C final amplifier

19. - E4E07

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

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

20. - E5A02

What is resonance in an electrical circuit?

Select	Answer
A	The lowest frequency that will pass current
B	The frequency at which the capacitive reactance equals the inductive reactance
C	The frequency at which the reactive impedance equals the resistive impedance
D	The highest frequency that will pass current

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage leading the current
B	68.2 degrees with the voltage leading the current
C	68.2 degrees with the voltage lagging the current
D	14.0 degrees with the voltage lagging the current

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

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In a direction opposite to the current
B	In a direction determined by the left-hand rule
C	In all directions; omni-directional
D	In the same direction as the current

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to gate current
B	The change of base current with respect to collector current
C	The change of collector current with respect to base current
D	The change of collector current with respect to emitter current

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Controlled reverse avalanche voltage
B	Enhanced carrier retention time
C	Much higher reverse voltage breakdown
D	Less forward voltage drop

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To increase the sensitivity
B	To prevent input noise from causing unstable output signals
C	To allow the comparator to be used with AC input signal
D	To cause the output to change states continually

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

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It is used in a battery charger circuit
B	It samples an analog signal and passes it in stages from the input to the output
C	Its phase shift changes rapidly with frequency
D	It is a CMOS analog-to-digital converter

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	A lens and a photomultiplier
B	A frequency modulated helium-neon laser
C	An LED and a phototransistor
D	An amplitude modulated helium-neon laser

30. - E7A10

What is a truth table?

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

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

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

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a band-pass filter
B	It is a high-pass filter
C	It is a low-pass filter
D	It is a notch filter

33. - E7D12

What is the drop-out voltage of an analog voltage regulator?

Select	Answer
A	Minimum input voltage for rated power dissipation
B	Minimum input-to-output voltage required to maintain regulation
C	Maximum amount that the output voltage drops when the input voltage is varied over its specified range
D	Maximum amount that the output voltage may decrease at rated load

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A heterodyne suppressor
B	A de-emphasis network
C	An audio prescaler
D	A pre-emphasis network

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

Select	Answer
A	It notches out the sampling frequency to avoid sampling errors
B	It removes high-frequency signal components which would otherwise be reproduced as lower frequency components
C	It peaks the response of the decimator, improving bandwidth
D	It removes low frequency signal components to eliminate the need for DC restoration

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 logarithmically with increasing frequency
C	It increases linearly with increasing frequency
D	It decreases linearly with increasing frequency

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Toroidal inductors
B	Wirewound resistors
C	NP0 capacitors
D	Non-inductive resistors

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. - E8B10

What describes frequency division multiplexing?

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

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, a retransmission is requested
B	Special polynomial codes provide automatic correction
C	If errors are detected, redundant data is substituted
D	Special binary codes provide automatic correction

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
B	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
C	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
D	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It is essentially unaffected
B	It decreases
C	It increases geometrically
D	It increases arithmetically

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	The E-field and H-field patterns may reverse
B	Feed point impedance may become negative
C	The gain may change depending on frequency
D	Element spacing limits could be exceeded

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band trap antenna
B	A phased array antenna consisting of multiple loops
C	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
D	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun

45. - E9D03

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

Select	Answer
A	As low as possible on the vertical radiator
B	At a voltage node
C	Near the center of the vertical radiator
D	As close to the transmitter as possible

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	Double-bazooka match
B	All of these choices are correct
C	Hairpin match
D	Gamma match

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	The same as the input impedance to the final generator stage
C	A capacitive reactance
D	An inductive reactance

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Frequency
B	Points with constant resistance
C	Points with constant reactance
D	SWR

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It receives equally well in all directions
B	It has a bidirectional pattern
C	It is non-rotatable
D	It is practical for use only on VHF bands

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

Select	Answer
A	Microwaves often travel long distances by ionospheric reflection
B	The extremely high frequency energy can damage the joints of antenna structures
C	Microwaves are ionizing radiation
D	The high gain antennas commonly used can result in high exposure levels