US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Ensure signals from your station are less than the uncontrolled Maximum Permitted Exposure (MPE) limits
B	Ensure signals from your station are less than the uncontrolled Maximum Permitted Emission (MPE) limits
C	Ensure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits
D	Ensure signals from your station are less than the controlled Maximum Permitted Exposure (MPE) limits

2. - E1A01

Which of the following carrier frequencies is illegal for LSB AFSK emissions on the 17 meter band RTTY and data segment of 18.068 to 18.110 MHz?

Select	Answer
A	18.068 MHz
B	18.107 MHz
C	18.100 MHz
D	18.110 MHz

3. - E1B03

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

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

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

Select	Answer
A	A special endorsement must be requested from the FCC
B	Operators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
C	Operators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station
D	An environmental impact statement must be filed with the Department of the Interior

5. - E1D10

Which amateur stations are eligible to be telecommand stations of space stations (subject to the privileges of the class of operator license held by the control operator of the station)?

Select	Answer
A	Any amateur station so designated by the ITU
B	All these choices are correct
C	Any amateur station so designated by the space station licensee
D	Any amateur station designated by NASA

6. - 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	Send the application form to the FCC and inform the FCC of the grade
C	Destroy the application form
D	Maintain the application form with the VEC's records

7. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and west of the U.S. Atlantic coastline
B	A line roughly parallel to and east of the U.S. Pacific coastline
C	A line roughly parallel to and south of the border between the U.S. and Canada
D	A line roughly parallel to and north of the border between the U.S. and Mexico

8. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	Power limits for uplink and downlink transmissions
B	The polarization of uplink and downlink signals
C	The uplink and downlink frequency ranges
D	The location of the ground control station

9. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
B	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
C	A type of modulation in which one sideband is inverted
D	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation

10. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?

Select	Answer
A	At the top of each band, usually in a segment reserved for contests
B	In the weak signal segment of the band, with most of the activity near the calling frequency
C	In the middle of the band, usually 25 kHz above the national calling frequency
D	In the middle of each band, usually on the national calling frequency

11. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	802.11
B	AMTOR
C	AX.25
D	PACTOR

12. - E2E12

How do ALE stations establish contact?

Select	Answer
A	ALE radios activate when they hear their signal echoed by back scatter
B	ALE radios send a constant tone code to establish a frequency for future use
C	ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received
D	ALE radios monitor an internet site for the frequency they are being paged on

13. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Urban areas
B	Mountain ranges
C	Forests
D	Bodies of water

14. - E3B07

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become elliptically polarized
B	They are bent toward the magnetic poles
C	They become depolarized
D	They become phase locked

15. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	D-region skip
B	Downward bending due to density variations in the atmosphere
C	Due to the Doppler effect
D	E-region skip

16. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	All these choices are correct
B	Antenna analyzers do not need an external RF source
C	Antenna analyzers automatically tune your antenna for resonance
D	Antenna analyzers display a time-varying representation of the modulation envelope

17. - E4B05

What three test loads are used to calibrate an RF vector network analyzer?

Select	Answer
A	Short circuit, open circuit, and resonant circuit
B	50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
C	50 ohms, 75 ohms, and 90 ohms
D	Short circuit, open circuit, and 50 ohms

18. - E4C03

What is the term for the suppression in an FM receiver of one signal by another stronger signal on the same frequency?

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

19. - 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 band-pass filter in the feed line between the transmitter and receiver
B	Utilizing a Class C final amplifier
C	Utilizing a Class D final amplifier
D	A properly terminated circulator at the output of the repeater's transmitter

20. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
B	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
C	By installing a noise suppression resistor and a blocking capacitor in both leads
D	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead

21. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	Minimum
B	L/R
C	Maximum
D	R/L

22. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	14 degrees with the voltage lagging the current
B	14 degrees with the voltage leading the current
C	76 degrees with the voltage leading the current
D	76 degrees with the voltage lagging the current

23. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By phase angle and magnitude
B	By Y and G values
C	By X and R values
D	By real and imaginary parts

24. - E5D08

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	1000 watts
B	200 watts
C	1600 watts
D	600 watts

25. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter voltage of approximately 6 to 7 volts
B	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
C	Base-to-emitter voltage of approximately 0.6 to 0.7 volts
D	Base-to-emitter resistance of approximately 6 to 7 ohms

26. - E6B06

Which of the following is a common use of a Schottky diode?

Select	Answer
A	As a variable capacitance in an automatic frequency control circuit
B	As a rectifier in high current power supplies
C	As a constant voltage reference in a power supply
D	As a VHF/UHF mixer or detector

27. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A type of transistor whose gain can be changed by digital logic circuits
B	A programmable collection of logic gates and circuits in a single integrated circuit
C	A logic circuit that can be modified during use
D	Programmable equipment used for testing digital logic integrated circuits

28. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	The skin effect
B	Inter-turn capacitance
C	Inductive kickback
D	Non-linear core hysteresis

29. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
B	Nearly infinite gain, very high input impedance, and very low output impedance
C	Plate current that is controlled by a control grid
D	The ability to retrieve information from a single signal even in the presence of other strong signals

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

Select	Answer
A	0.1 V
B	0.5 V
C	12 V
D	1.5 V

31. - E7A10

What is a truth table?

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

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

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

33. - E7C08

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

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

34. - E7D08

What type of circuit is shown in Figure E7-2?

Select	Answer
A	Monostable multivibrator
B	Linear voltage regulator
C	Grounded emitter amplifier
D	Switching voltage regulator

35. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	For higher efficiency
B	To remove third-order distortion products
C	To reduce impulse noise reception
D	For compatibility with transmitters using phase modulation

36. - 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 that 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

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	-2.3 volts
B	0.23 volts
C	-0.23 volts
D	2.3 volts

38. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Increase the bias voltage
B	Reduce noise on the oscillator's power supply
C	Mechanically isolate the oscillator circuitry from its enclosure
D	Use NP0 capacitors

39. - 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	25 to 1
D	1 to 1

40. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	2.14
B	0.214
C	0.47
D	47

41. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The number of control characters in a message packet
B	The rate at which the waveform changes to convey information
C	The duration of each bit in a message sent over the air
D	The number of characters carried per second by the station-to-station link

42. - E8D06

What is the advantage of including parity bits in ASCII characters?

Select	Answer
A	The signal can overpower interfering signals
B	Faster transmission rate
C	Foreign language characters can be sent
D	Some types of errors can be detected

43. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	Distance from the transmitter
B	Soil conductivity
C	Take-off angle
D	The standing wave ratio

44. - E9B05

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

Select	Answer
A	Polarization
B	Azimuth
C	Radiation resistance
D	Elevation

45. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

Select	Answer
A	Omni-directional
B	A figure-8 oriented along the axis of the array
C	A figure-8 broadside to the axis of the array
D	Cardioid

46. - 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	As close to the transmitter as possible
D	Near the center of the vertical radiator

47. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To transform the antenna impedance to a higher value
B	To provide DC isolation between the feed line and the antenna
C	To cancel the inductive reactance of the matching network
D	To provide a rejection notch that prevents the radiation of harmonics

48. - E9F11

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

Select	Answer
A	A capacitive reactance
B	The same as the characteristic impedance of the line
C	Infinite
D	An inductive reactance

49. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and reactance
B	Reactance and voltage
C	Resistance and voltage
D	Voltage and impedance

50. - E9H05

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

Select	Answer
A	It has a bidirectional pattern
B	All these choices are correct
C	It has no clearly defined null
D	It is practical for use only on VHF and higher bands

Figure E7-2

Figure E7-3

Figure E9-2