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

2. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

Select	Answer
A	Only a person named in an amateur station license grant
B	Only a person with an FCC Marine Radio license grant
C	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
D	Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit

3. - E1B11

What does PRB-1 require of regulations affecting amateur radio?

Select	Answer
A	Reasonable accommodations of amateur radio must be made
B	No limitations may be placed on antenna size or placement
C	Amateur radio operations must be permitted in any private residence
D	Use of wireless devices in a vehicle is exempt from regulation

4. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	5 minutes
B	30 seconds
C	10 minutes
D	3 minutes

5. - E1D03

What is a space telecommand station?

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

6. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The VEC coordinating the session
B	The VE session manager
C	Each administering VE
D	The FCC

7. - E1F09

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

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

8. - 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 linearly polarized antenna
C	A circularly polarized antenna
D	A log-periodic dipole array

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

10. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To separate the calling stations from the DX station
B	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
C	To improve operating efficiency by reducing interference
D	All these choices are correct

11. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
C	All these choices are correct
D	An APRS station with a Global Positioning System unit can automatically transmit information to show a mobile station's position during the event

12. - E2E03

How is the timing of FT4 contacts organized?

Select	Answer
A	Stations take turns on alternate days
B	By exchanging ACK/NAK packets
C	Alternating transmissions at 7.5 second intervals
D	It depends on the lunar phase

13. - E3A13

Which of these emission modes is best for auroral propagation?

Select	Answer
A	FM
B	CW
C	RTTY
D	SSB

14. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	Only 30 meters to 10 meters
B	160 meters to 10 meters
C	6 meters to 2 meters
D	Only 160 meters to 40 meters

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	Evaluating high voltage sources for x-rays
D	Modeling a radio wave's path through the ionosphere

16. - E4A04

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
B	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
C	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

17. - E4B02

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
B	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
C	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
D	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

Select	Answer
A	Multiple frequencies can be received simultaneously if desired
B	Receive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference
C	The noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity
D	Receiver power consumption can be reduced when wider bandwidth is not required

19. - E4D11

Why are odd-order intermodulation products, created within a receiver, of particular interest compared to other products?

Select	Answer
A	Odd-order products overload the IF filters
B	Odd-order intermodulation produces three products for every input signal within the band of interest
C	Odd-order products of two signals in the band of interest are also likely to be within the band
D	Odd-order products are an indication of poor image rejection

20. - E4E06

What is one type of electrical interference that might be caused by a nearby personal computer?

Select	Answer
A	A loud AC hum in the audio output of your station receiver
B	A clicking noise at intervals of a few seconds
C	The appearance of unstable modulated or unmodulated signals at specific frequencies
D	A whining type noise that continually pulses off and on

21. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It equals 2 multiplied by pi, multiplied by frequency, multiplied by inductance
B	It is at a maximum
C	It equals 1 divided by the quantity 2 times pi, multiplied by the square root of inductance L multiplied by capacitance C
D	It is at a minimum

22. - E5B06

What is susceptance?

Select	Answer
A	The ratio of magnetic field to electric field
B	A measure of the efficiency of a transformer
C	The magnetic impedance of a circuit
D	The imaginary part of admittance

23. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A positive magnitude
B	A positive phase angle
C	A negative phase angle
D	A negative magnitude

24. - E5D15

What is the power factor of an RL circuit having a 45-degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.707
C	0.5
D	1.0

25. - E6A05

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	An FET has lower input impedance
B	They are both low impedance
C	An FET has higher input impedance
D	They are both high impedance

26. - E6B06

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

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

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 type of transistor whose gain can be changed by digital logic circuits
C	A logic circuit that can be modified during use
D	Programmable equipment used for testing digital logic integrated circuits

28. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores confine most of the magnetic field within the core material
B	Toroidal cores exhibit greater hysteresis
C	Toroidal cores have lower Q characteristics
D	Toroidal cores make it easier to couple the magnetic energy into other components

29. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

Select	Answer
A	-20 dBm
B	2 dB
C	-10 dB
D	44 dBm

30. - E6F07

What is a solid-state relay?

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

31. - E7A02

What is the function of a decade counter?

Select	Answer
A	It produces 10 output pulses for every input pulse
B	It decodes a decimal number for display on a seven-segment LED display
C	It decodes a binary number for display on a seven-segment LED display
D	It produces one output pulse for every 10 input pulses

32. - E7B01

For what portion of the signal cycle does each active element in a push-pull Class AB amplifier conduct?

Select	Answer
A	More than 180 degrees but less than 360 degrees
B	Less than 180 degrees
C	The entire cycle
D	Exactly 180 degrees

33. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Gradual passband rolloff with minimal stop band ripple
B	Extremely sharp cutoff with one or more notches in the stop band
C	Extremely flat response over its pass band with gradually rounded stop band corners
D	Gradual passband rolloff with extreme stop band ripple

34. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-2?

Select	Answer
A	To provide fixed DC bias for Q1
B	It bypasses rectifier output ripple around D1
C	To self-resonate at the hum frequency
D	It is a brute force filter for the output

35. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By driving a product detector with a DSB signal
B	By using a loop modulator followed by a mixer
C	By using a reactance modulator followed by a mixer
D	By using a balanced modulator followed by a filter

36. - E7F11

What sets the minimum detectable signal level for a direct-sampling SDR receiver in the absence of atmospheric or thermal noise?

Select	Answer
A	Data storage transfer rate
B	Sample clock phase noise
C	Reference voltage level and sample width in bits
D	Missing codes and jitter

37. - 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

38. - E7H08

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

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

39. - E8A05

What of the following instruments would be the most accurate for measuring the RMS voltage of a complex waveform?

Select	Answer
A	A D'Arsonval meter
B	A true-RMS calculating meter
C	An absorption wave meter
D	A grid dip meter

40. - E8B10

What is 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

41. - E8C05

What is the approximate bandwidth of a 13-WPM International Morse Code transmission?

Select	Answer
A	26 Hz
B	52 Hz
C	104 Hz
D	13 Hz

42. - E8D05

What is the most common method of reducing key clicks?

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

43. - E9A13

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Half-power bandwidth
B	Power factor
C	Effective radiated power
D	Apparent power

44. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

Select	Answer
A	The computed feed point impedance may be incorrect
B	The antenna will become mechanically unstable
C	The resulting design will favor radiation of harmonic energy
D	Ground conductivity will not be accurately modeled

45. - E9C05

Which of the following is a type of OCFD antenna?

Select	Answer
A	A dipole fed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
B	A multiband dipole antenna using one-way circular polarization for frequency diversity
C	A remotely tunable dipole antenna using orthogonally controlled frequency diversity
D	A folded dipole center-fed with 300-ohm transmission line

46. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	Gain is reduced
B	SWR bandwidth decreases
C	SWR bandwidth increases
D	More common-mode current is present on the feed line

47. - E9E10

Which of these choices is an effective way to match an antenna with a 100-ohm feed point impedance to a 50-ohm coaxial cable feed line?

Select	Answer
A	Connect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna
B	Insert a 1/4-wavelength piece of 75-ohm coaxial cable transmission line in series between the antenna terminals and the 50-ohm feed cable
C	Insert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable
D	Connect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna

48. - 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	Zero
B	A capacitive reactance
C	An inductive reactance
D	The same as the characteristic impedance of the line

49. - 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

50. - E9H04

What is an advantage of placing a grounded electrostatic shield around a small loop direction-finding antenna?

Select	Answer
A	It adds capacitive loading, increasing the bandwidth of the antenna
B	It eliminates unbalanced capacitive coupling to the surroundings, improving the nulls
C	It increases signal strength by providing a better match to the feed line
D	It eliminates tracking errors caused by strong out-of-band signals

Figure E7-2