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

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1. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Ingestion of ozone gas from the cooling system
B	Hearing loss caused by high voltage corona discharge
C	Localized heating of the body from RF exposure in excess of the MPE limits
D	Blood clotting from the intense magnetic field

2. - E1A07

What is the maximum power permitted on the 2200 meter band?

Select	Answer
A	100 watts PEP
B	1 watt EIRP (Equivalent isotropic radiated power)
C	5 watts EIRP (Equivalent isotropic radiated power)
D	50 watts PEP

3. - E1B12

What must the control operator of a repeater operating in the 70 cm band do if a radiolocation system experiences interference from that repeater?

Select	Answer
A	Cease operation or make changes to the repeater to mitigate the interference
B	File an FAA NOTAM (Notice to Airmen) with the repeater system's ERP, call sign, and six-character grid locator
C	All these choices are correct
D	Reduce the repeater antenna HAAT (Height Above Average Terrain)

4. - E1C13

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

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

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

Select	Answer
A	2 watts
B	5 watts
C	100 watts
D	1 watt

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

7. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	440 MHz - 450 MHz
B	222 MHz - 223 MHz
C	420 MHz - 430 MHz
D	53 MHz - 54 MHz

8. - E2A05

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

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

9. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To provide vertical synchronization
B	To lock the color burst oscillator in color SSTV images
C	To identify the call sign of the station transmitting
D	To identify the SSTV mode being used

10. - E2C09

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

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

11. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	Storing and forwarding digital messages
B	Judging optimum transmission times by monitoring beacons reflected from the moon
C	High-speed CW identification to avoid fading
D	Time synchronous transmissions alternately from each station

12. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PACTOR
B	PSK31
C	MT63
D	RTTY

13. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Temperature inversion
B	The jet stream
C	Wind shear
D	Dust devil

14. - E3B09

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

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

15. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	NVIS
B	Transequatorial
C	Sporadic E
D	Polar

16. - E4A11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Select	Answer
A	Connect the antenna feed line directly to the analyzer's connector
B	Loosely couple the analyzer near the antenna base
C	Connect the analyzer via a high-impedance transformer to the antenna
D	Loosely couple the antenna and a dummy load to the analyzer

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 a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
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 an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit

18. - E4C12

Which of the following has the largest effect on an SDR receiver's dynamic range?

Select	Answer
A	Analog-to-digital converter sample width in bits
B	CPU register width in bits
C	Anti-aliasing input filter bandwidth
D	RAM speed used for data storage

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. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

Select	Answer
A	All these choices are correct
B	Power line noise
C	Broadband white noise
D	Ignition noise

21. - E5A10

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

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

22. - E5B03

How is impedance in polar form converted to an equivalent admittance?

Select	Answer
A	Take the reciprocal of the angle and change the sign of the magnitude
B	Square the magnitude and subtract 90 degrees from the angle
C	Take the reciprocal of the magnitude and change the sign of the angle
D	Take the square root of the magnitude and add 180 degrees to the angle

23. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Phasor diagram
B	Venn diagram
C	Far field diagram
D	Near field diagram

24. - E5D11

What is the power factor of an RL circuit having a 60-degree phase angle between the voltage and the current?

Select	Answer
A	0.5
B	0.866
C	1.73
D	1.414

25. - E6A11

In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	1
B	2
C	3
D	6

26. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant current drop under conditions of varying voltage
B	A negative resistance region
C	An internal capacitance that varies with the applied voltage
D	A constant voltage drop under conditions of varying current

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	4
B	2
C	3
D	1

28. - E6D13

What is the primary cause of inductor self-resonance?

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

29. - E6E05

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

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

30. - E6F10

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

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

31. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic 1 at its output only if all inputs are logic 1
B	It produces logic 0 at its output if only one input is logic 1
C	It produces logic 1 at its output if only one input is logic 1
D	It produces logic 0 at its output only if all inputs are logic 0

32. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Self bias
B	Fixed bias
C	Output load resistor
D	Emitter bypass

33. - E7C07

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50-ohm unbalanced output?

Select	Answer
A	A Phase Inverter Load network
B	A matching network in which all components are isolated from ground
C	A network with only three discrete parts
D	A Pi-network with an additional series inductor on the output

34. - E7D11

What is the function of the pass transistor in a linear voltage regulator circuit?

Select	Answer
A	Maintains nearly constant output voltage over a wide range of load current
B	Provides a stable input impedance over a wide range of source voltage
C	Permits a wide range of output voltage settings
D	Maintains nearly constant output impedance over a wide range of load current

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

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

36. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At least twice the rate of the highest frequency component of the signal
B	At least half the rate of the highest frequency component of the signal
C	At four times the rate of the highest frequency component of the signal
D	At the same rate as the highest frequency component of the signal

37. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 1800 ohms and RF is 68 kilohms?

Select	Answer
A	1
B	76
C	38
D	0.03

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a quartz crystal
B	Through a neutralizing capacitor
C	Through a tapped coil
D	Through link coupling

39. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all its harmonics?

Select	Answer
A	A sawtooth wave
B	A cosine wave
C	A sine wave
D	A square wave

40. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more signals are arranged to share discrete time slots of a data transmission
B	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
C	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
D	Two or more signals are quadrature modulated to increase bandwidth efficiency

41. - E8C05

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

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

42. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Ground loops
B	Bit errors in the modem
C	Excessive numbers of retries
D	Excessive transmit audio levels

43. - E9A04

Which of the following factors affect the feed point impedance of an antenna?

Select	Answer
A	The input power level
B	The settings of an antenna tuner at the transmitter
C	Transmission line length
D	Antenna height

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

Select	Answer
A	38 dB
B	28 dB
C	15 dB
D	3 dB

45. - E9C06

What is the effect of adding a terminating resistor to a rhombic antenna?

Select	Answer
A	It changes the radiation pattern from horizontal to vertical polarization
B	It changes the radiation pattern from bidirectional to unidirectional
C	It reflects the standing waves on the antenna elements back to the transmitter
D	It decreases the ground loss

46. - E9D05

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

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

47. - E9E08

What is a use for a Wilkinson divider?

Select	Answer
A	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
B	It is used to divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance
C	It is used to feed high-impedance antennas from a low-impedance source
D	It is used to feed low-impedance loads from a high-impedance source

48. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	The surge impedance is higher in a parallel feed line
B	Skin effect is less pronounced in the coaxial cable
C	Electrical signals move more slowly in a coaxial cable than in air
D	The characteristic impedance is higher in a parallel feed line

49. - E9G05

Which of the following is a common use for a Smith chart?

Select	Answer
A	Determine the length and position of an impedance matching stub
B	Determine the loss/100 feet of a transmission line, given the velocity factor and conductor materials
C	Determine the impedance of a transmission line, given the physical dimensions
D	Determine the gain of an antenna given the physical and electrical parameters

50. - E9H04

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

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

Figure E6-1

Figure E6-3

Figure E7-1

Figure E7-3