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 Exposure (MPE) limits
D	Ensure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits

2. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	100 watts PEP effective radiated power relative to an isotropic radiator
B	50 watts PEP effective radiated power relative to an isotropic radiator
C	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
D	50 watts PEP effective radiated power relative to a dipole

3. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	An emission outside the signal's necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
B	A signal transmitted to prevent its detection by any station other than the intended recipient
C	An amateur station transmission made without the proper call sign identification
D	Any transmitted signal that unintentionally interferes with another licensed radio station

4. - E1C02

Which of the following types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	All these choices are correct
B	Messages intended for users of the maritime satellite service
C	Communications incidental to the purpose of the amateur service and remarks of a personal nature
D	Business-related messages for non-profit organizations

5. - E1D03

What is a space telecommand station?

Select	Answer
A	An amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
B	An amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth
C	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
D	An amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites

6. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	Photocopy all examination documents and forward them to the FCC for processing
B	Issue the examinee the new or upgrade license
C	All these choices are correct
D	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements

7. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When the total money involved does not exceed $25
B	When neither the amateur nor his or her employer has a pecuniary interest in the communications
C	When the control operator is employed by the FCC or another government agency
D	When transmitting international third-party communications

8. - E2A09

What do the terms L band and S band specify regarding satellite communications?

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

9. - E2B05

Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?

Select	Answer
A	The vestigial sideband carries the audio information
B	Vestigial sideband provides high frequency emphasis to sharpen the picture
C	The vestigial sideband contains chroma information
D	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry

10. - E2C09

What type of equipment is commonly used to implement an amateur radio mesh network?

Select	Answer
A	A 440 MHz transceiver with a 9600 baud modem
B	A 2 meter VHF transceiver with a 1200 baud modem
C	A wireless router running custom firmware
D	An optical cable connection between the USB ports of 2 separate computers

11. - E2D09

What type of modulation is used for JT65 contacts?

Select	Answer
A	IEEE 802.11
B	Multi-tone AFSK
C	RTTY
D	PSK

12. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	First Error Correction
B	Fatal Error Correction
C	Final Error Correction
D	Forward Error Correction

13. - E3A05

Tropospheric propagation of microwave signals often occurs in association with what phenomenon?

Select	Answer
A	Warm and cold fronts
B	Sprites and jets
C	Grayline
D	Lightning discharges

14. - E3B11

At what time of day can sporadic E propagation occur?

Select	Answer
A	Only in hours of darkness
B	Only around sunset and sunrise
C	Any time
D	Only around sunset

15. - E3C01

What does the radio communication term "ray tracing" describe?

Select	Answer
A	The process in which an electronic display presents a pattern
B	Determining the radiation pattern from an array of antennas
C	Modeling a radio wave's path through the ionosphere
D	Evaluating high voltage sources for x-rays

16. - E4A01

Which of the following limits the highest frequency signal that can be accurately displayed on a digital oscilloscope?

Select	Answer
A	All these choices are correct
B	Q of the circuit
C	Sampling rate of the analog-to-digital converter
D	Amount of memory

17. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Input attenuator accuracy
B	Temperature coefficient of the logic
C	Decade divider accuracy
D	Time base accuracy

18. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	One-half the maximum sampling buffer size
B	The reference voltage of the analog-to-digital converter
C	One-half the maximum sample rate
D	The maximum count value of the analog-to-digital converter

19. - E4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

Select	Answer
A	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
B	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
C	Spurious signals caused by cross-modulation and desensitization from strong adjacent signals
D	Oscillator instability and severe audio distortion of all but the strongest received signals

20. - E4E01

What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals?

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

21. - E5A13

What is an effect of increasing Q in a series resonant circuit?

Select	Answer
A	Fewer components are needed for the same performance
B	Internal voltages increase
C	Parasitic effects are minimized
D	Phase shift can become uncontrolled

22. - E5B04

What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors, all in parallel?

Select	Answer
A	55 seconds
B	220 seconds
C	110 seconds
D	440 seconds

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

Select	Answer
A	The X axis represents the resistive component and the Y axis represents the reactive component
B	The X axis represents the reactive component and the Y axis represents the resistive component
C	The X axis represents the phase angle and the Y axis represents the magnitude
D	The X axis represents the magnitude and the Y axis represents the phase angle

24. - E5D14

What is reactive power?

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

25. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To reduce the chance of static damage to the gate
B	To provide a voltage reference for the correct amount of reverse-bias gate voltage
C	To protect the substrate from excessive voltages
D	To keep the gate voltage within specifications and prevent the device from overheating

26. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Insufficient forward voltage
B	Charge carrier depletion
C	Excessive junction temperature
D	Excessive inverse voltage

27. - E6C09

What is a Programmable Logic Device (PLD)?

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

28. - E6D06

What core material property determines the inductance of an inductor?

Select	Answer
A	Resistance
B	Permeability
C	Reactivity
D	Thermal impedance

29. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Surface mount
B	Radial lead
C	TO-220
D	Axial lead

30. - E6F10

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

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

31. - E7A01

Which circuit is bistable?

Select	Answer
A	An OR gate
B	A bipolar amplifier
C	An AND gate
D	A flip-flop

32. - 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 distortion and excessive bandwidth
C	Reduced intermodulation products
D	Signal inversion

33. - 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	Reactive currents are dissipated in matched resistances
D	It introduces transconductance to cancel the reactive part of impedance

34. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A shunt current source
B	A series regulator
C	A shunt regulator
D	A series current source

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

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

36. - E7F07

What function is performed by a Fast Fourier Transform?

Select	Answer
A	Converting digital signals from the time domain to the frequency domain
B	Converting digital signals to analog form
C	Converting analog signals to digital form
D	Converting 8-bit data to 16-bit data

37. - E7G03

What is the typical input impedance of an op-amp?

Select	Answer
A	100 ohms
B	1000 ohms
C	Very high
D	Very low

38. - E7H08

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

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

39. - E8A06

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

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

40. - E8B01

What is the modulation index of an FM signal?

Select	Answer
A	The ratio of frequency deviation to modulating signal frequency
B	The bandwidth of the transmitted signal divided by the modulating signal frequency
C	The type of modulation used by the transmitter
D	The ratio of modulating signal amplitude to frequency deviation

41. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is twice the symbol rate
B	Baud is only used for RTTY
C	Symbol rate is only used for packet-based modes
D	They are the same

42. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Increase keying waveform rise and fall times
B	Reduce keying waveform rise and fall times
C	High-pass filters at the transmitter output
D	Low-pass filters at the transmitter output

43. - E9A03

What is the radiation resistance of an antenna?

Select	Answer
A	The specific impedance of the antenna
B	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
C	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
D	The combined losses of the antenna elements and feed line

44. - E9B08

What is the far field of an antenna?

Select	Answer
A	The region where the shape of the antenna pattern is independent of distance
B	The region of the ionosphere where radiated power is not refracted
C	The region where radiated power dissipates over a specified time period
D	The region where radiated field strengths are constant

45. - E9C09

Which of the following describes a G5RV antenna?

Select	Answer
A	A phased array antenna consisting of multiple loops
B	A multi-band trap antenna
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

46. - E9D10

What happens to feed-point impedance at the base of a fixed length HF mobile antenna when operated below its resonant frequency?

Select	Answer
A	The radiation resistance decreases and the capacitive reactance decreases
B	The radiation resistance increases and the capacitive reactance decreases
C	The radiation resistance decreases and the capacitive reactance increases
D	The radiation resistance increases and the capacitive reactance increases

47. - E9E01

What system matches a higher-impedance transmission line to a lower-impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The gamma matching system
B	The delta matching system
C	The omega matching system
D	The stub matching system

48. - E9F12

What impedance does a 1/4-wavelength transmission line present to a generator when the line is open at the far end?

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

49. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Prime axis
B	Polar axis
C	Impedance axis
D	Reactance axis

50. - E9H03

What is Receiving Directivity Factor (RDF)?

Select	Answer
A	Relative directivity compared to a dipole
B	Forward gain compared to the gain in the reverse direction
C	Forward gain compared to average gain over the entire hemisphere
D	Relative directivity compared to isotropic

Figure E9-3