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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	1 kHz above the lower band edge
B	3 kHz above the lower band edge
C	The exact lower band edge
D	300 Hz above the lower band edge

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 53 dB below
B	At least 73 dB below
C	At least 43 dB below
D	At least 63 dB below

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

Select	Answer
A	Only auxiliary, repeater or space stations
B	Only beacon, repeater or space stations
C	Only auxiliary, beacon or space stations
D	Only earth stations, repeater stations or model craft

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	Any amateur station designated by NASA
C	All of these choices are correct
D	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

Select	Answer
A	In a question pool maintained by the FCC
B	In the appropriate FCC Report and Order
C	In FCC Part 97
D	In a question pool maintained by all the VECs

6. - 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. Extra Class privileges
B	All privileges of the Extra Class license
C	None, they must obtain a U.S. license
D	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	29.5 MHz - 29.7 MHz
B	50.0 MHz - 50.2 MHz
C	144 MHz - 146 MHz
D	435 MHz - 438 MHz

8. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

Select	Answer
A	2 MHz
B	6 MHz
C	3 kHz
D	600 Hz

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

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

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	PACTOR III
B	JT65
C	Olivia
D	FSK441

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Final Error Correction
B	First Error Correction
C	Fatal Error Correction
D	Forward Error Correction

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves produced by a loop antenna
B	Waves with a rotating electric field
C	Waves with an electric field bent into a circular shape
D	Waves that circle the Earth

13. - E3B14

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

Select	Answer
A	They are bent toward the magnetic poles
B	They become phase-locked
C	Their polarization is randomly modified
D	They become elliptically polarized

14. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	Waning sunspot numbers
B	An extreme geomagnetic storm
C	Moderate solar wind
D	Very low solar activity

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

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

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S11
B	S21
C	S12
D	S22

17. - E4C07

What does the MDS of a receiver represent?

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

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To provide a range of AGC time constants
B	To allow selection of the optimum RF amplifier device
C	To store often-used frequencies
D	To increase rejection of unwanted signals

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	A malfunctioning illuminated advertising display
B	Arcing contacts in a thermostatically controlled device
C	A defective doorbell or doorbell transformer inside a nearby residence
D	All of these choices are correct

20. - E5A15

Which of the following can increase Q for inductors and capacitors?

Select	Answer
A	Lower self-resonant frequency
B	Higher self-resonant frequency
C	Lower losses
D	Lower reactance

21. - 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?

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

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The magnitude and phase of the point
B	The tangent and cotangent values
C	The sine and cosine values
D	The coordinate values along the horizontal and vertical axes

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In a direction opposite to the current
B	In the same direction as the current
C	In a direction determined by the left-hand rule
D	In all directions; omni-directional

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Holes
B	Free protons
C	Free electrons
D	Free neutrons

25. - E6B11

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

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

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	An integrated circuit logic family using both bipolar and CMOS transistors
B	A logic device with two CMOS circuits per package
C	A logic family based on bismuth CMOS devices
D	A FET logic family based on bimetallic semiconductors

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	Harmonics and distortion could result
B	RF susceptance would increase
C	Temporary changes of the core permeability could result
D	Magnetic flux would increase with frequency

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Direct soldering
B	Virtual lead mounting
C	Stripped lead
D	Surface mount

29. - E6F08

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

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

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic "1" at its output only if all inputs are logic "1"
B	It produces logic "1" at its output if any single input is logic "1"
C	It produces logic "0" at its output only if all inputs are logic "0"
D	It produces logic "0" at its output if any single input is logic "1"

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	Low input impedance
B	High power gain
C	High filament voltage
D	Low bandwidth

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a high-pass filter
B	It is a notch filter
C	It is a low-pass filter
D	It is a band-pass filter

33. - E7D13

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

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

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	An audio prescaler
B	A pre-emphasis network
C	A heterodyne suppressor
D	A de-emphasis network

35. - 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

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. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a voltage-controlled oscillator and the output waveform
B	The phase relationship between a reference oscillator and the output waveform
C	The synthesizer frequency limits and frequency values stored in the radio memories
D	The amplitude values that represent a sine-wave output

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	8 multiplied by the gain of the input amplifier
B	8
C	256 divided by the gain of the input amplifier
D	256

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	2.14
B	0.47
C	0.214
D	47

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By transmitting a special algorithm to the receiving station along with the data characters
B	By varying the frequency shift of the transmitted signal according to a predefined algorithm
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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Ground loops
B	Bit errors in the modem
C	Excessive transmit audio levels
D	Excessive numbers of retries

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	6.17 dB
B	12.5 dB
C	14.15 dB
D	9.85 dB

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region where radiated field strengths are obstructed by objects of reflection
B	The region where radiated power dissipates over a specified time period
C	The region of the ionosphere where radiated power is not refracted
D	The region where the shape of the antenna pattern is independent of distance

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It changes the impedance angle of the matching network
B	It reduces losses in the radiating portion of the antenna
C	It reduces low-angle radiation
D	It causes increased SWR

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	A single 12 gauge or 10 gauge stainless steel wire
B	A resistive wire, such as spark plug wire
C	A wide flat copper strap
D	A cable with six or seven 18 gauge conductors in parallel

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

47. - E9F14

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

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It is electro statically balanced against ground, giving better nulls
B	It eliminates tracking errors caused by strong out-of-band signals
C	It allows stations to communicate without giving away their position
D	It automatically cancels ignition noise in mobile installations

50. - E0A01

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

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