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

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

Select	Answer
A	The location is of environmental importance or significant in American history, architecture, or culture
B	The location is near an area of political conflict
C	The location is in an ITU Zone designated for coordination with one or more foreign governments
D	The location is of geographical or horticultural importance

3. - E1C07

What is meant by local control?

Select	Answer
A	Direct manipulation of the transmitter by a control operator
B	Automatically manipulating local station controls
C	Controlling a repeater using a portable handheld transceiver
D	Controlling a station through a local auxiliary link

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

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	Photocopy all examination documents and forward them to the FCC for processing
B	Issue the examinee the new or upgrade license
C	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
D	All these choices are correct

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 50 MHz
B	Only on amateur frequencies above 144 MHz
C	Only on amateur frequencies above 222 MHz
D	Only on amateur frequencies above 420 MHz

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Radar
B	Bandwidth compressed LORAN
C	APRS
D	Doppler shift of beacon signals

8. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	120
B	30
C	60
D	90

9. - E2C06

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

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

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	High speed CW identification to avoid fading
B	Time synchronous transmissions alternately from each station
C	Judging optimum transmission times by monitoring beacons reflected from the Moon
D	Storing and forwarding digital messages

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	2.16 kHz
B	316 Hz
C	31 Hz
D	550 Hz

12. - E3A12

What is the cause of auroral activity?

Select	Answer
A	The interaction in the F2 layer between the solar wind and the Van Allen belt
B	The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
C	A low sunspot level combined with tropospheric ducting
D	Meteor showers concentrated in the extreme northern and southern latitudes

13. - E3B05

Which amateur bands typically support long-path propagation?

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

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	An increase in the critical frequency
B	Higher levels of solar UV radiation
C	Decreasing disruption of the geomagnetic field
D	Increasing disruption of the geomagnetic field

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	SWR and time
B	RF amplitude and frequency
C	SWR and frequency
D	RF amplitude and time

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	0.1 MHz
B	14.652 Hz
C	1.4652 Hz
D	1.4652 kHz

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It limits the receiver's ability to receive strong signals
B	It decreases receiver third-order intermodulation distortion dynamic range
C	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
D	It reduces receiver sensitivity

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

Select	Answer
A	Amplifier desensitization
B	Adjacent channel interference
C	Neutralization
D	Intermodulation interference

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
B	By installing a noise suppression resistor and a blocking capacitor in both leads
C	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
D	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Parasitic effects are minimized
B	Internal voltages and circulating currents increase
C	Phase shift can become uncontrolled
D	Fewer components are needed for the same performance

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

Select	Answer
A	It is unchanged
B	The sign is reversed
C	The susceptance phase angle is the inverse of the reactance phase angle
D	It is shifted by 90 degrees

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A positive phase angle
B	A negative real part
C	A negative phase angle
D	A positive real part

23. - E5D08

What type of energy is stored in an electromagnetic or electrostatic field?

Select	Answer
A	Electromechanical energy
B	Potential energy
C	Kinetic energy
D	Thermodynamic energy

24. - E6A16

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

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

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Zener diode
B	Silicon-controlled rectifier
C	Tunnel diode
D	Varactor diode

26. - E6C03

What is tri-state logic?

Select	Answer
A	Low power logic devices designed to operate at 3 volts
B	Logic devices with 0, 1, and high impedance output states
C	Proprietary logic devices manufactured by Tri-State Devices
D	Logic devices that utilize ternary math

27. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Select	Answer
A	Powdered-iron cores generally maintain their characteristics at higher currents
B	Powdered-iron cores generally require fewer turns to produce a given inductance
C	Powdered-iron cores generally have greater initial permeability
D	Powdered-iron cores use smaller diameter wire for the same inductance

28. - E6E08

How is voltage from a power supply normally furnished to the most common type of monolithic microwave integrated circuit (MMIC)?

Select	Answer
A	Through a capacitor and RF choke connected to the amplifier input lead
B	Directly to the bias voltage (VCC IN) lead
C	MMICs require no operating bias
D	Through a resistor and/or RF choke connected to the amplifier output lead

29. - E6F11

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

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

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	A flip-flop
B	An "OR" gate
C	A clock
D	An "AND" gate

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Output load resistor
B	Emitter bypass
C	Fixed bias
D	Self bias

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	An automatic notch filter
B	A special filter that emphasizes image responses
C	A variable bandwidth crystal lattice filter
D	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

Select	Answer
A	A shunt current source
B	A series regulator
C	A constant current source
D	A shunt regulator

34. - E7E05

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

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

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

Select	Answer
A	It peaks the response of the decimator, improving bandwidth
B	It notches out the sampling frequency to avoid sampling errors
C	It removes high-frequency signal components which would otherwise be reproduced as lower frequency components
D	It removes low frequency signal components to eliminate the need for DC restoration

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The output voltage of the op-amp minus its input voltage
B	The differential input voltage needed to bring the open loop output voltage to zero
C	The potential between the amplifier input terminals of the op-amp in an open loop condition
D	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Bias the crystal at a specified voltage
B	Bias the crystal at a specified current
C	Provide the crystal with a specified parallel capacitance
D	Provide the crystal with a specified parallel inductance

38. - E8A12

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

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

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal jumps from band to band at a predetermined rate
B	The transmitted signal is divided into packets of information
C	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
D	Two or more information streams are merged into a baseband, which then modulates the transmitter

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

Select	Answer
A	It is easier to demodulate with a conventional, non-synchronous detector
B	This results in the least possible transmitted bandwidth for the particular mode
C	It improves carrier suppression
D	All of these choices are correct

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
B	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
C	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
D	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Shorten the radiating element
B	Isolate the coax shield from ground
C	Reduce the diameter of the radiating element
D	Install a good radial system

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	25 degrees
B	45 degrees
C	75 degrees
D	7.5 degrees

44. - E9C13

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

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

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to a metal water pipe
B	A 50 ohm resistor connected to ground
C	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
D	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Connect a parallel-resonant LC network across the antenna feed terminals
B	Connect a series-resonant LC network across the antenna feed terminals
C	Use the universal stub matching technique
D	Use a 50 ohm 1:1 balun between the antenna and feed line

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

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Reactance axis
B	Polar axis
C	Impedance axis
D	Prime axis

49. - 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	Atmospheric noise is so high that gain over a dipole is not important
C	They must be erected at least 1/2 wavelength above the ground to attain good directivity
D	All of these choices are correct

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Uranium Hexafluoride
B	Beryllium Oxide
C	Mica
D	Zinc oxide

Figure E7-1

Figure E9-2

Figure E9-3