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

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1. - E1A01

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

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

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in New Mexico surrounding the White Sands Test Area
B	An area in Puerto Rico surrounding the Arecibo Radio Telescope
C	An area surrounding the National Radio Astronomy Observatory
D	An area in Florida surrounding Cape Canaveral

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	You must append "/CEPT" to your call sign
B	You must identify in the official language of the country in which you are operating
C	The U.S. embassy must approve of your operation
D	You must bring a copy of FCC Public Notice DA 11-221

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
B	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
D	All HF bands

5. - E1E12

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

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

6. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
B	A line roughly parallel to and east of the U.S. Pacific coastline
C	A line roughly parallel to and west of the U.S. Atlantic coastline
D	A line roughly parallel to and south of the U.S.-Canadian border

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geomagnetic
B	Geostationary
C	HEO
D	LEO

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are not permitted above 54 MHz
B	None; they are allowed on all amateur frequencies
C	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
D	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 440 MHz transceiver with a 9600 baud modem
B	A 2 meter VHF transceiver with a 1200 baud modem
C	An optical cable connection between the USB ports of 2 separate computers
D	A standard wireless router running custom software

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	It can decode signals many dB below the noise floor using FEC
B	It supplies signals to guide the antenna to track the Moon
C	All of these choices are correct
D	It controls the receiver to track Doppler shift

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	MT63
B	RTTY
C	PACTOR
D	PSK31

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
B	A wave of alternating current, in the core of an electromagnet
C	A wave consisting of two magnetic fields at right angles to each other
D	A wave consisting of two electric fields at parallel right angles to each other

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	160 meters to 40 meters
B	6 meters to 2 meters
C	160 meters to 10 meters
D	30 meters to 10 meters

14. - E3C11

What does VOACAP software model?

Select	Answer
A	HF propagation
B	AC voltage and impedance
C	VHF radio propagation
D	AC current and impedance

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

Select	Answer
A	Sampling rate
B	Input impedance
C	Sample resolution
D	Input capacitance

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	14.652 kHz
B	165.2 Hz
C	1.4652 MHz
D	146.52 Hz

17. - E4C05

What does a value of -174 dBm/Hz represent with regard to the noise floor of a receiver?

Select	Answer
A	The noise figure of a 1 Hz bandwidth receiver
B	The galactic noise contribution to minimum detectable signal
C	The theoretical noise at the input of a perfect receiver at room temperature
D	The minimum detectable signal as a function of receive frequency

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	The third-order product of two signals which are in the band of interest is also likely to be within the band
D	Third-order intermodulation produces three products for every input signal within the band of interest

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	The broadcast station is transmitting an over-modulated signal
B	Your station receiver IF amplifier stage is defective
C	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
D	You are receiving sky wave signals from a distant station

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It is at a maximum
B	It is at a minimum
C	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
D	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	55 seconds
B	110 seconds
C	220 seconds
D	440 seconds

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Rectangular coordinates
B	Maidenhead grid
C	Faraday grid
D	Elliptical coordinates

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	1.414
C	1.73
D	0.5

24. - E6A16

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

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

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Controlled reverse avalanche voltage
B	Much higher reverse voltage breakdown
C	Enhanced carrier retention time
D	Less forward voltage drop

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To prevent input noise from causing unstable output signals
B	To allow the comparator to be used with AC input signal
C	To increase the sensitivity
D	To cause the output to change states continually

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

Select	Answer
A	Teflon and Delrin
B	Polystyrene and polyethylene
C	Ferrite and brass
D	Cobalt and aluminum

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It is used in a battery charger circuit
B	Its phase shift changes rapidly with frequency
C	It samples an analog signal and passes it in stages from the input to the output
D	It is a CMOS analog-to-digital converter

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The output RF power divided by the input DC power
B	The open-circuit voltage divided by the short-circuit current under full illumination
C	The effective payback period
D	The relative fraction of light that is converted to current

30. - E7A12

What type of logic defines "0" as a high voltage?

Select	Answer
A	Positive Logic
B	Reverse Logic
C	Assertive Logic
D	Negative logic

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

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

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

Select	Answer
A	Video
B	Single-Sideband voice
C	Digital
D	Meteor scatter

33. - E7D16

When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?

Select	Answer
A	To equalize, as much as possible, the voltage drop across each capacitor
B	All of these choices are correct
C	To provide a minimum load current to reduce voltage excursions at light loads
D	To provide a safety bleeder to discharge the capacitors when the supply is off

34. - E7E10

How does a diode detector function?

Select	Answer
A	By sensing the change of reactance in the diode with respect to frequency
B	By breakdown of the Zener voltage
C	By rectification and filtering of RF signals
D	By mixing signals with noise in the transition region of the diode

35. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	Combine signals with a quadrature phase relationship
B	Emulation of quartz crystal filter characteristics
C	A frequency synthesizer removes the unwanted sidebands
D	Mixing products are converted to voltages and subtracted by adder circuits

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	94
B	24
C	0.21
D	47

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A hybrid synthesizer
B	A phase locked loop synthesizer
C	A diode-switching matrix synthesizer
D	A direct digital synthesizer

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	All of these choices are correct
C	Digital signals always occupy a narrower bandwidth
D	Digital signals can be regenerated multiple times without error

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	FM compressibility
B	Quieting index
C	Modulation index
D	Percentage of modulation

40. - E8C11

What is the relationship between symbol rate and baud?

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to change frequencies
B	The receiver is always equipped with a digital blanker
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered

42. - E9A17

What is the effective radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

Select	Answer
A	252 watts
B	632 watts
C	159 watts
D	63.2 watts

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	14 dB
B	36 dB
C	24 dB
D	18 dB

44. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The lobes become more perpendicular to the wire
B	The vertical angle increases
C	The front-to-back ratio decreases
D	The lobes align more in the direction of the wire

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To cancel capacitive reactance
B	To increase the SWR bandwidth
C	To lower the Q
D	To lower the losses

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

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

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

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radio propagation
B	Antenna radiation pattern
C	Impedance along transmission lines
D	Radiation resistance

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A large circularly polarized antenna
B	A vertical antenna coupled to a feed line through an inductive loop of wire
C	One or more turns of wire wound in the shape of a large open coil
D	A small coil of wire tightly wound around a toroidal ferrite core

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	You need only evaluate exposure levels on your own property
B	Advise your neighbors of the results of your tests
C	Make sure signals from your station are less than the controlled MPE limits
D	Make sure signals from your station are less than the uncontrolled MPE limits

Figure E7-4

Figure E9-1