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

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1. - E0A08

What does SAR measure?

Select	Answer
A	Signal Amplification Rating
B	The rate of RF energy reflected from stationary terrain
C	The rate at which RF energy is absorbed by the body
D	Synthetic Aperture Ratio of the human body

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

3. - E1B07

To what type of regulations does PRB-1 apply?

Select	Answer
A	FAA tower height limits
B	Homeowners associations
C	Use of wireless devices in vehicles
D	State and local zoning

4. - E1C07

At what level below a signal's mean power level is its bandwidth determined according to FCC rules?

Select	Answer
A	23 dB
B	3 dB
C	6 dB
D	26 dB

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of General, Advanced or Amateur Extra Class operators
B	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
C	Any amateur station, subject to the privileges of the class of operator license held by the control operator
D	Only those of Amateur Extra Class operators

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	Send the application form to the FCC and inform the FCC of the grade
D	Maintain the application form with the VEC's records

7. - E1F10

Who may be the control operator of an auxiliary station?

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

8. - E2A02

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

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

9. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	A type of modulation in which one sideband is inverted
B	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
C	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
D	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier

10. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Contacts between a U.S. station and a non-U.S. station
B	Contacts using tactical call signs
C	Special event contacts between stations in the U.S.
D	Repeater contacts between U.S. club members

11. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	All these choices are correct
B	Short transmissions with rapidly repeated call signs and signal reports
C	15-second timed transmission sequences with stations alternating based on location
D	Use of special digital modes

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	It depends on the lunar phase
D	Alternating transmissions at 7.5 second intervals

13. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Bodies of water
B	Forests
C	Mountain ranges
D	Urban areas

14. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	80 meters
B	10 meters
C	6 meters
D	20 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. - E4A11

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

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

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
B	Modulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
C	Modulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
D	Modulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter

18. - E4C07

What does the MDS of a receiver represent?

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

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 are an indication of poor image rejection
D	Odd-order products of two signals in the band of interest are also likely to be within the band

20. - E4E02

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

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

21. - E5A05

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

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

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 6
B	Point 4
C	Point 5
D	Point 2

24. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	All these choices are correct
B	To increase the thermal time constant
C	To avoid unwanted inductive reactance
D	To maintain component lifetime

25. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Insulator impurity
B	Acceptor impurity
C	Donor impurity
D	N-type impurity

26. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Capacitance of an RF coupling capacitor
B	A sub-harmonic pump signal
C	Reverse voltage larger than the RF signal
D	Forward DC bias current

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	Its simplicity results in much less expensive devices than standard CMOS
B	It is immune to electrostatic damage
C	All these choices are correct
D	It has the high input impedance of CMOS and the low output impedance of bipolar transistors

28. - E6D12

What is inductor saturation?

Select	Answer
A	Adjacent inductors become over-coupled
B	The inductor windings are over-coupled
C	The inductor's voltage rating is exceeded causing a flashover
D	The ability of the inductor's core to store magnetic energy has been exceeded

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

Select	Answer
A	Unsuitable for combining analog and digital signals
B	Too many pins
C	Excessive lead length
D	Epoxy coating is conductive above 300 MHz

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

Select	Answer
A	0.5 V
B	0.1 V
C	12 V
D	1.5 V

31. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Monostable multivibrator
B	T flip-flop
C	Astable multivibrator
D	J-K flip-flop

32. - E7B01

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

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

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 network with only three discrete parts
C	A Pi-network with an additional series inductor on the output
D	A Phase Inverter Load network

34. - E7D11

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

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

35. - E7E09

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

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

36. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A phase-inverting filter
B	A crystal-lattice filter
C	A Hilbert-transform filter
D	An adaptive filter

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	94
C	0.21
D	24

38. - E7H02

What is a microphonic?

Select	Answer
A	An IC used for amplifying microphone signals
B	Excess loading of the microphone by an oscillator
C	Changes in oscillator frequency due to mechanical vibration
D	Distortion caused by RF pickup on the microphone cable

39. - E8A06

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

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

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	0.167
B	1.67
C	60
D	0.6

41. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By varying the frequency shift of the transmitted signal according to a predefined algorithm
B	By transmitting a special algorithm to the receiving station along with the data characters
C	By the receiving station repeating each block of three data characters
D	By transmitting extra data that may be used to detect and correct transmission errors

42. - E8D09

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

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

43. - E9A10

Which of the following improves the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	All these choices are correct
B	Shortening the radiating element
C	Isolating the coax shield from ground
D	Installing a radial system

44. - E9B10

What is the principle of a Method of Moments analysis?

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

45. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

Select	Answer
A	A figure-8 oriented along the axis of the array
B	A figure-8 broadside to the axis of the array
C	Cardioid
D	Omni-directional

46. - E9D05

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

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

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

Select	Answer
A	62 ohms
B	450 ohms
C	75 ohms
D	50 ohms

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

49. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning prime center with regard to the reactance axis
B	Reassigning resistance values with regard to the reactance axis
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning impedance values with regard to the prime center

50. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	Low loss coax transmission line is essential for good performance
B	They must be erected at least 1/2 wavelength above the ground to attain good directivity
C	Atmospheric noise is so high that gain over a dipole is not important
D	All these choices are correct

Figure E5-1