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 Exposure (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 uncontrolled Maximum Permitted Emission (MPE) limits

2. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
B	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use
C	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
D	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply

3. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historic Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	A letter of intent must be filed with the Environmental Protection Agency
C	A proposal must be submitted to the National Park Service
D	An Environmental Assessment must be submitted to the FCC

4. - E1C01

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	170 Hz
B	2.8 kHz
C	1.5 kHz
D	60 Hz

5. - E1D04

Which of the following is required in the identification transmissions from a balloon-borne telemetry station?

Select	Answer
A	Call sign
B	The station's six-character Maidenhead grid locator
C	The output power of the balloon transmitter
D	All these choices are correct

6. - E1E06

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

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

7. - E1F10

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only General, Advanced or Amateur Extra Class operators
B	Only Technician, General, Advanced or Amateur Extra Class operators
C	Any licensed amateur operator
D	Only Amateur Extra Class operators

8. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

Select	Answer
A	All these choices are correct
B	FM and CW
C	SSB and SSTV
D	PSK and packet

9. - E2B05

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

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

10. - E2C02

Which of the following best describes the term self-spotting? in connection with HF contest operating?

Select	Answer
A	The often-prohibited practice of posting one's own call sign and frequency on a spotting network
B	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
C	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
D	The acceptable practice of manually posting the call signs of stations on a spotting network

11. - E2D01

Which of the following digital modes is designed for meteor scatter communications?

Select	Answer
A	MSK144
B	WSPR
C	Hellschreiber
D	APRS

12. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	AMTOR
B	Hellschreiber
C	RTTY
D	PACTOR

13. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The F2 layer
B	The E layer
C	The D layer
D	The F1 layer

14. - E3B05

Which amateur bands typically support long-path propagation?

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

15. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class M
B	Class B
C	Class A
D	Class X

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	SWR and time
B	RF amplitude and frequency
C	RF amplitude and time
D	SWR and frequency

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. - 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	Capture effect
B	Desensitization
C	Cross-modulation interference
D	Frequency discrimination

19. - E4D06

What is the term for spurious signals generated by the combination of two or more signals in a non-linear device or circuit?

Select	Answer
A	Intermodulation
B	Amplifier desensitization
C	Adjacent channel interference
D	Neutralization

20. - E4E08

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Return current
B	Reactive current only
C	Common-mode current
D	Differential-mode current

21. - E5A09

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

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

22. - E5B12

What is admittance?

Select	Answer
A	The turns ratio of a transformer
B	The term for the gain of a field effect transistor
C	The inverse of impedance
D	The inverse of Q factor

23. - E5C10

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 400-ohm resistor and a 38-picofarad capacitor at 14 MHz?

Select	Answer
A	Point 5
B	Point 2
C	Point 6
D	Point 4

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. - E6A07

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

Select	Answer
A	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
B	Base-to-emitter voltage of approximately 6 to 7 volts
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. - E6B03

What type of bias is required for an LED to emit light?

Select	Answer
A	Reverse bias
B	Inductive bias
C	Zero bias
D	Forward bias

27. - E6C10

In Figure E6-3, what is the schematic symbol for a NOR gate?

Select	Answer
A	4
B	2
C	3
D	1

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

Select	Answer
A	Brass
B	Ferrite
C	Powdered iron
D	Ceramic

29. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	Ball grid array
B	PLCC
C	DIP
D	SOT

30. - E6F06

Which of these materials is most commonly used to create photoconductive devices?

Select	Answer
A	A heavy metal
B	A liquid semiconductor
C	An ordinary metal
D	A crystalline semiconductor

31. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It stores one bit of data in either a 0 or 1 state
B	It switches momentarily to the opposite binary state and then returns to its original state after a set time
C	It produces a continuous square wave oscillating between 1 and 0
D	It maintains a constant output voltage, regardless of variations in the input voltage

32. - E7B06

Which of the following amplifier types reduces even-order harmonics?

Select	Answer
A	Class C
B	Class AB
C	Push-push
D	Push-pull

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

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. - 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 detecting FM signals
D	A circuit for filtering two closely adjacent signals

36. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

Select	Answer
A	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
B	Software is converted from source code to object code during operation of the receiver
C	Incoming RF is converted to a control voltage for a voltage controlled oscillator
D	A switching mixer is used to generate I and Q signals directly from the RF input

37. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E73 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	47
B	0.21
C	94
D	24

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

Select	Answer
A	Pierce, Fenner and Beane
B	Colpitts, Hartley and Pierce
C	Taft, Hartley and Pierce
D	Taft, Pierce and negative feedback

39. - E8A04

What is "dither" with respect to analog-to-digital converters?

Select	Answer
A	An abnormal condition where the converter cannot settle on a value to represent the signal
B	An error caused by irregular quantization step size
C	A method of decimation by randomly skipping samples
D	A small amount of noise added to the input signal to allow more precise representation of a signal over time

40. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	3
B	0.3
C	1000
D	3000

41. - E8C03

Why should phase-shifting of a PSK signal be done at the zero crossing of the RF signal?

Select	Answer
A	All these choices are correct
B	To improve carrier suppression
C	To simplify modulation
D	To minimize bandwidth

42. - E8D08

What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

Select	Answer
A	Signal-to-noise ratio
B	Baud rate
C	Repeat Request Rate (RRR)
D	Intermodulation Distortion (IMD)

43. - E9A04

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

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

44. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a single sine-wave voltage source
B	A wire is modeled as a series of segments, each having a uniform value of current
C	A wire is modeled as a series of segments, each having a distinct value of voltage across it
D	A wire is modeled as a single sine-wave current generator

45. - E9C06

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

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

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

47. - E9E05

How must an antenna's driven element be tuned to use a hairpin matching system?

Select	Answer
A	The driven element reactance must be inductive
B	The driven element resonance must be lower than the operating frequency
C	The driven element reactance must be capacitive
D	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line

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	Infinite
C	The same as the characteristic impedance of the line
D	An inductive reactance

49. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Antenna radiation pattern
B	Impedance along transmission lines
C	Radio propagation
D	Radiation resistance

50. - E9H03

What is Receiving Directivity Factor (RDF)?

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

Figure E5-1

Figure E6-3

Figure E7-2