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

2. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the highest frequency of the channel
B	At the center frequency of the channel
C	At the lowest frequency of the channel
D	On any frequency where the signal's sidebands are within the channel

3. - E1B09

Which amateur stations may be operated under RACES rules?

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

4. - E1C09

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	2.0
B	1.0
C	3.0
D	0.5

5. - E1D06

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

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

6. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	The person who has entered into an agreement with the FCC to be the VE session manager
B	A person who has volunteered to prepare amateur operator license examinations
C	An organization that has entered into an agreement with the FCC to coordinate, prepare, and administer amateur operator license examinations
D	A person who has volunteered to administer amateur operator license examinations

7. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the government of Canada?

Select	Answer
A	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Amateur Extra Class license privileges
B	Full privileges, up to and including those of the Amateur Extra Class license, on the 80, 40, 20, 15, and 10 meter bands
C	None, they must obtain a U.S. license
D	All privileges of the Amateur Extra Class license

8. - E2A09

What do the terms L band and S band specify regarding satellite communications?

Select	Answer
A	The 2 meter and 70 centimeter bands
B	Which sideband to use
C	The 23 centimeter and 13 centimeter bands
D	FM and Digital Store-and-Forward systems

9. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	525
B	30
C	1080
D	60

10. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?

Select	Answer
A	In the middle of each band, usually on the national calling frequency
B	In the middle of the band, usually 25 kHz above the national calling frequency
C	At the top of each band, usually in a segment reserved for contests
D	In the weak signal segment of the band, with most of the activity near the calling frequency

11. - E2D01

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

Select	Answer
A	APRS
B	Hellschreiber
C	WSPR
D	MSK144

12. - E2E08

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

Select	Answer
A	AMTOR
B	PACTOR
C	RTTY
D	Hellschreiber

13. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the MUF is above 30 MHz
B	When the moon is full
C	When the moon is at perigee
D	When the moon is at apogee

14. - E3B11

At what time of day can sporadic E propagation occur?

Select	Answer
A	Only in hours of darkness
B	Only around sunset and sunrise
C	Any time
D	Only around sunset

15. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Vertical
B	Circular
C	Elliptical
D	Horizontal

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Bit error rate tester
B	Modulation monitor
C	Network analyzer
D	Logic analyzer

17. - E4B04

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

Select	Answer
A	S21
B	S12
C	S22
D	S11

18. - E4C02

Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

Select	Answer
A	A properly adjusted product detector
B	A notch filter
C	A narrow IF filter
D	A front-end filter or pre-selector

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

20. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals that have a sharply peaked frequency distribution
B	Signals that appear at one IF but not another
C	Signals that appear across a wide bandwidth
D	Signals that are constant at all IF levels

21. - E5A09

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

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

22. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage or to discharge to 36.8% of its initial voltage?

Select	Answer
A	One exponential period
B	One time constant
C	An exponential rate of one
D	A time factor of one

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	Near field diagram
D	Far field diagram

24. - E5D14

What is reactive power?

Select	Answer
A	Power lost because of capacitor leakage
B	Wattless, nonproductive power
C	Power consumed in wire resistance in an inductor
D	Power consumed in circuit Q

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	5
B	2
C	6
D	4

26. - E6B11

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

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

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

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

28. - E6D06

What core material property determines the inductance of an inductor?

Select	Answer
A	Reactivity
B	Thermal impedance
C	Resistance
D	Permeability

29. - E6E01

Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

Select	Answer
A	Lower junction voltage drop
B	Higher electron mobility
C	Lower transconductance
D	Higher noise figures

30. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of electrical energy to mechanical energy
B	The conversion of light to electrical energy
C	The conversion of voltage to current when exposed to light
D	The tendency of a battery to discharge when exposed to light

31. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic 1 at its output if all inputs are logic 0
B	It only produces logic 0 at its output when all inputs are logic 1
C	It produces logic 0 at its output if all inputs are logic 1
D	It produces logic 1 at its output if any or all inputs are logic 1

32. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common collector
B	Common base
C	Emitter follower
D	Common emitter

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 gain of the RF stage preceding the filter
D	The relative frequencies of the individual crystals

34. - E7D08

What type of circuit is shown in Figure E7-2?

Select	Answer
A	Monostable multivibrator
B	Linear voltage regulator
C	Grounded emitter amplifier
D	Switching voltage regulator

35. - E7E09

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

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

36. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	To reduce excess signal pressure levels
B	Provide incremental signal delays for filter algorithms
C	Provide access for debugging software
D	Select the point at which baseband signals are generated

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	-0.23 volts
B	0.23 volts
C	2.3 volts
D	-2.3 volts

38. - E7H10

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

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

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 grid dip meter
C	An absorption wave meter
D	A true-RMS calculating meter

40. - E8B09

What is deviation ratio?

Select	Answer
A	The ratio of the highest audio modulating frequency to the average audio modulating frequency
B	The ratio of the audio modulating frequency to the center carrier frequency
C	The ratio of the carrier center frequency to the audio modulating frequency
D	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency

41. - E8C10

How may data rate be increased without increasing bandwidth?

Select	Answer
A	Using forward error correction
B	Increasing analog-to-digital conversion resolution
C	It is impossible
D	Using a more efficient digital code

42. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It contains fewer information bits per character than any other code
B	It includes built-in error correction features
C	It is possible to transmit both upper and lower case text
D	It uses one character as a shift code to send numeric and special characters

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	2000 watts
B	317 watts
C	126 watts
D	300 watts

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Mutual impedance analysis
B	Method of Moments
C	Graphical analysis
D	Calculus differentiation with respect to physical properties

45. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A type of ground-plane antenna
B	A half-wave dipole with an additional parallel wire connecting its two ends
C	A dipole configured to provide forward gain
D	A dipole one-quarter wavelength long

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
B	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
C	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
D	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase

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 omega match
B	The delta match
C	The stub match
D	The gamma match

48. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
B	The index of shielding for coaxial cable
C	The ratio of the characteristic impedance of the line to the terminating impedance
D	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum

49. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Coaxial-length circles
B	Antenna-length circles
C	Standing wave ratio circles
D	Radiation-pattern circles

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 increases signal strength by providing a better match to the feed line
C	It eliminates unbalanced capacitive coupling to the surroundings, improving the nulls
D	It adds capacitive loading, increasing the bandwidth of the antenna

Figure E6-1

Figure E7-1

Figure E7-2

Figure E7-3