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 controlled Maximum Permitted Emission (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 uncontrolled Maximum Permitted Emission (MPE) limits
D	Ensure signals from your station are less than the uncontrolled Maximum Permitted Exposure (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	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
C	50 watts PEP effective radiated power relative to an isotropic radiator
D	50 watts PEP effective radiated power relative to a dipole

3. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Only those club stations licensed to Amateur Extra Class operators
B	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
C	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
D	Any FCC-licensed amateur station except a Technician Class

4. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control there is no control operator
B	Under local control there is no control operator
C	Under automatic control the control operator is not required to be present at the control point
D	Under local control a control operator is not required to be present at a control point

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

6. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Destroy the application form
B	Return the application document to the examinee
C	Maintain the application form with the VEC's records
D	Send the application form to the FCC and inform the FCC of the grade

7. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide temporary operation while awaiting normal licensing
B	To provide for experimental amateur communications
C	To allow regular operation on Land Mobile channels
D	To provide additional spectrum for personal use

8. - E2A02

Which of the following occurs when a satellite is using an inverting linear transponder?

Select	Answer
A	Signal position in the band is reversed
B	All these choices are correct
C	Doppler shift is reduced because the uplink and downlink shifts are in opposite directions
D	Upper sideband on the uplink becomes lower sideband on the downlink, and vice versa

9. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	120
B	30
C	60
D	90

10. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	6 meters
B	33 centimeters
C	30 meters
D	2 meters

11. - E2D04

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Ultrasonics
B	Doppler shift of beacon signals
C	APRS
D	Bandwidth compressed LORAN

12. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	Selective fading has occurred
B	The receiver has drifted 5 kHz from the desired receive frequency
C	One of the signal filters is saturated
D	The mark and space signal have been inverted

13. - E3A12

What is the cause of auroral activity?

Select	Answer
A	The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
B	An extreme low-pressure area in the polar regions
C	The interaction in the F2 layer between the solar wind and the Van Allen belt
D	Meteor showers concentrated in the extreme northern and southern latitudes

14. - E3B07

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

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

15. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the sun will cause disturbed conditions?

Select	Answer
A	Westward
B	Southward
C	Northward
D	Eastward

16. - E4A08

Which of the following measures SWR?

Select	Answer
A	A spectrum analyzer
B	A Q meter
C	An ohmmeter
D	An antenna analyzer

17. - E4B04

Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

Select	Answer
A	S12
B	S11
C	S21
D	S22

18. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The maximum detectable spectrum
B	The minimum discernible signal
C	The multiplex distortion stability
D	The meter display sensitivity

19. - E4D02

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

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

20. - E4E02

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

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

21. - E5A05

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	Matching bandwidth is increased
B	Matching bandwidth is decreased
C	It has no effect on impedance matching
D	Matching range is increased

22. - E5B05

What happens to the magnitude of a pure reactance when it is converted to a susceptance?

Select	Answer
A	It is shifted by 90 degrees
B	It becomes the reciprocal
C	It is unchanged
D	The sign is reversed

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 6
B	Point 2
C	Point 5
D	Point 4

24. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as heat in the circuit
B	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
C	It is dissipated in the formation of inductive and capacitive fields
D	It is dissipated as kinetic energy in the circuit

25. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	N-type
B	P-type
C	Bipolar
D	Insulated gate

26. - E6B03

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

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

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

28. - E6D13

What is the primary cause of inductor self-resonance?

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

29. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	10 ohms
B	50 ohms
C	450 ohms
D	300 ohms

30. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	An LED and a phototransistor
B	An amplitude modulated helium-neon laser
C	A lens and a photomultiplier
D	A frequency modulated helium-neon laser

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 table of logic symbols that indicate the logic states of an op-amp
D	A diagram showing logic states when the digital device output is true

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	Signal distortion and excessive bandwidth
B	Increased overall intelligibility
C	Signal inversion
D	Reduced intermodulation products

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

34. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Matching of day and night charge rates
B	Control of electrolyte levels during battery discharge
C	Prevention of battery damage due to overcharge
D	Prevention of battery undercharge

35. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	A beat frequency is generated
B	Automatic limiting occurs
C	Mixer blanking occurs
D	Spurious mixer products are generated

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. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	7
B	0.07
C	14
D	28

38. - E7H10

What information is contained in the lookup table of a direct digital synthesizer (DDS)?

Select	Answer
A	Amplitude values that represent the desired waveform
B	The phase relationship between a reference oscillator and the output waveform
C	Frequently used receiver and transmitter frequencies
D	The phase relationship between a voltage-controlled oscillator and the output waveform

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	25 to 1
C	2.5 to 1
D	1 to 1

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	3000
B	3
C	1000
D	0.3

41. - E8C11

What is the relationship between symbol rate and baud?

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

42. - E8D09

What is considered an acceptable maximum IMD level for an idling PSK signal?

Select	Answer
A	+15 dB
B	-30 dB
C	+10 dB
D	-20 dB

43. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Radiation resistance plus transmission resistance
B	Radiation resistance plus loss resistance
C	Transmission-line resistance plus radiation resistance
D	Radiation resistance plus space impedance

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

45. - E9C03

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

Select	Answer
A	A Figure-8 broadside to the axis of the array
B	Omni-directional
C	Cardioid
D	A Figure-8 end-fire along the axis of the array

46. - E9D05

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

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

47. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The delta match
B	The gamma match
C	The stub match
D	The omega match

48. - E9F04

What impedance does a 1/2-wavelength transmission line present to a generator when the line is shorted at the far end?

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

49. - E9G04

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

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

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

Select	Answer
A	High radiation angle
B	Broadband response
C	A very sharp peak
D	A very sharp single null

Figure E5-1

Figure E7-3