US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - 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	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
C	Only a person named in an amateur station license grant
D	Only a person with an FCC Marine Radio

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	30 miles
C	3 miles
D	1 mile

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	3 minutes
B	30 seconds
C	5 minutes
D	10 minutes

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
B	An amateur station located more than 50 km above the Earth's surface
C	An amateur station that transmits telemetry consisting of measurements of upper atmosphere
D	An amateur station that transmits communications to initiate, modify or terminate functions of a space station

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	Teaching an amateur operator license examination preparation course
B	Providing amateur operator license examination preparation training materials
C	No expenses are authorized for reimbursement
D	Preparing, processing, administering and coordinating an examination for an amateur radio license

6. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When transmitting international third-party communications
B	When the total money involved does not exceed $25
C	When the control operator is employed by the FCC or another government agency
D	When neither the amateur nor his or her employer has a pecuniary interest in the communications

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From east to west
B	From north to south
C	From west to east
D	From south to north

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Spectral Intensity
B	Luminance
C	Chroma
D	Hue

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Every contest requires a signal report in the exchange
B	Interference to other amateurs is unavoidable and therefore acceptable
C	Operators are permitted to make contacts even if they do not submit a log
D	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	Hellschreiber
B	FSK441
C	WSPR
D	APRS

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	PSK31
B	170 Hz shift, 45 baud RTTY
C	MFSK16
D	300-baud packet

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	28 MHz - 148 MHz
B	10 MHz - 14 MHz
C	1.8 MHz - 1.9 MHz
D	220 MHz - 450 MHz

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between any two points located on the magnetic equator
B	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
C	Propagation between two stations at the same latitude
D	Propagation between two continents by way of ducts along the magnetic equator

14. - E3C05

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

Select	Answer
A	Eastward
B	Northward
C	Westward
D	Southward

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A logic analyzer
B	A time-domain reflectometer
C	A spectrum analyzer
D	A wattmeter

16. - E4B15

Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?

Select	Answer
A	The resonant frequency of the circuit
B	The inductance to capacitance ratio
C	The bandwidth of the circuit's frequency response
D	The frequency shift

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Capture effect
B	Desensitization
C	Cross-modulation interference
D	Frequency discrimination

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	Third-order products are an indication of poor image rejection
B	The third-order intercept is much higher than other orders
C	Third-order intermodulation produces three products for every input signal within the band of interest
D	The third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E06

What is a major cause of atmospheric static?

Select	Answer
A	Thunderstorms
B	Geomagnetic storms
C	Meteor showers
D	Solar radio frequency emissions

20. - E5A17

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

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

21. - E5B09

What is the relationship between the current through a capacitor and the voltage across a capacitor?

Select	Answer
A	Voltage leads current by 90 degrees
B	Voltage and current are 180 degrees out of phase
C	Voltage and current are in phase
D	Current leads voltage by 90 degrees

22. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?

Select	Answer
A	The sum of the reactive and resistive components
B	Reactive component
C	The difference between the resistive and reactive components
D	Resistive component

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By dividing the apparent power by the power factor
B	By multiplying the apparent power times the power factor
C	By dividing the reactive power by the power factor
D	By multiplying the reactive power times the power factor

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to gate current
B	The change of base current with respect to collector current
C	The change of collector current with respect to emitter current
D	The change of collector current with respect to base current

25. - E6B13

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

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

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	A PGA contains its own internal power supply
B	Complex logic functions can be created in a single integrated circuit
C	All of these choices are correct
D	Many similar gates are less expensive than a mixture of gate types

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores confine most of the magnetic field within the core material
B	Toroidal cores exhibit greater hysteresis
C	Toroidal cores make it easier to couple the magnetic energy into other components
D	Toroidal cores have lower Q characteristics

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Point-to-point construction
B	Wave-soldering construction
C	Ground-plane construction
D	Microstrip construction

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators eliminate the effects of reflected light in the control circuit
B	Optoisolators provide a low impedance link between a control circuit and a power circuit
C	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
D	Optoisolators provide impedance matching between the control circuit and power circuit

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	A multiplexer
B	An OR gate
C	A flip-flop
D	An XOR gate

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A temperature compensating load resistor to improve linearity
B	A matched load resistor to prevent damage by switching transients
C	A low-pass filter to remove switching signal components
D	A high-pass filter to compensate for low gain at low frequencies

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Pi
B	Cascode
C	Omega
D	Pi-L

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage multiplied by input current
B	Output voltage multiplied by output current
C	Voltage difference from input to output multiplied by output current
D	Input voltage divided by output current

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	1.414 and 0.707 times the input frequency
B	The sum, difference and square root of the input frequencies
C	The two input frequencies along with their sum and difference frequencies
D	Two and four times the original frequency

35. - E7F01

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

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

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It increases linearly with increasing frequency
B	It does not vary with frequency
C	It decreases logarithmically with increasing frequency
D	It decreases linearly with increasing frequency

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Pierce and Zener
B	Colpitts and Hartley
C	Armstrong and deForest
D	Negative feedback and balanced feedback

38. - 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	100 to 1
C	25 to 1
D	1 to 1

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A frequency modulation technique which uses non-harmonically related frequencies
B	A digital mode for narrow band, slow speed transmissions
C	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
D	A bandwidth compression technique using Fourier transforms

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, redundant data is substituted
B	Special binary codes provide automatic correction
C	Special polynomial codes provide automatic correction
D	If errors are detected, a retransmission is requested

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

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

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

Select	Answer
A	420 watts
B	1977 watts
C	78.7 watts
D	286 watts

43. - E9B09

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

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

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A portable antenna erected using two push support poles
B	A wideband vertical antenna constructed from precisely tapered aluminum tubing
C	An end fed folded dipole antenna
D	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)

45. - E9D02

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

Select	Answer
A	Stack two Yagis fed 90 degrees out of 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	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
D	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
B	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna
C	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable
D	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	Foam dielectric has lower safe operating voltage limits
B	Foam dielectric has lower loss per unit of length
C	Foam dielectric has higher velocity factor
D	All of these choices are correct

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Frequency
B	Points with constant resistance
C	Points with constant reactance
D	SWR

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It allows DF antennas to receive signals at different vertical angles
B	It modifies the pattern of a DF antenna array to provide a null in one direction
C	It increases the sensitivity of a DF antenna array
D	It provides diversity reception that cancels multipath signals

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Lightning protection
B	Reduce RFI to telephones and home entertainment systems
C	Reduce RF current flow between pieces of equipment
D	Reduce received noise