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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
B	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
C	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
D	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use

2. - E1B05

What is the National Radio Quiet Zone?

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

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

Select	Answer
A	A control operator must be present at the control point
B	Only Extra Class operators may be the control operator of a remote station
C	A control operator need not be present at the control point
D	Repeater and auxiliary stations may not be remotely controlled

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
B	Only those of General, Advanced or Amateur Extra Class operators
C	Any amateur station, subject to the privileges of the class of operator license held by the control operator
D	Only those of Amateur Extra Class operators

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	A sentence of up to one year in prison
B	A fine of up to $1000 per occurrence
C	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
D	All of these choices are correct

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	420 MHz - 430 MHz
B	440 MHz - 450 MHz
C	222 MHz - 223 MHz
D	53 MHz - 54 MHz

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By means of the Doppler data for the specified satellite
B	By subtracting the mean anomaly from the orbital inclination
C	By calculations using the Keplerian elements for the specified satellite
D	By adding the mean anomaly to the orbital inclination

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	10 KHz
B	15 KHz
C	3 KHz
D	20 KHz

9. - E2C01

Which of the following is true about contest operating?

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

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
B	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
C	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
D	All of these choices are correct

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A slow change in the pitch of the CW signal
B	A gradual loss of signal as the Sun rises
C	The returning echo is several Hertz lower in frequency than the transmitted signal
D	A fluttery irregular fading

13. - E3B07

Which of the following could account for hearing an echo on the received signal of a distant station?

Select	Answer
A	Transmit frequency is higher than the MUF
B	High D layer absorption
C	Receipt of a signal by more than one path
D	Meteor scatter

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The solar emission at 304 GHz, correlated to X-Ray flare levels
B	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
C	UV emissions at 304 angstroms, correlated to solar flux index
D	The ratio of X-Ray flux to radio flux, correlated to sunspot number

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
B	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
C	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High impedance input
B	Low impedance input
C	High reluctance input
D	Low reluctance input

17. - E4C02

Which of the following portions of a receiver can be effective in eliminating image signal interference?

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

18. - E4D09

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

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

19. - E4E04

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

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

20. - E5A04

What is the magnitude of the impedance of a circuit with a resistor, an inductor and a capacitor all in parallel, at resonance?

Select	Answer
A	Low, as compared to the circuit resistance
B	Approximately equal to inductive reactance
C	Approximately equal to capacitive reactance
D	Approximately equal to circuit resistance

21. - E5B05

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

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

22. - E5C03

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

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

23. - E5D08

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

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

24. - E6A05

What is the alpha of a bipolar junction transistor?

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

25. - E6B12

What is one common use for PIN diodes?

Select	Answer
A	As a constant current source
B	As a high voltage rectifier
C	As a constant voltage source
D	As an RF switch

26. - E6C14

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

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

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

Select	Answer
A	79 turns
B	13 turns
C	35 turns
D	141 turns

28. - E6E10

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

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

29. - E6F04

What is the photovoltaic effect?

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

30. - E7A03

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

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

31. - E7B02

What is a Class D amplifier?

Select	Answer
A	A frequency doubling amplifier
B	A type of amplifier that uses switching technology to achieve high efficiency
C	A low power amplifier that uses a differential amplifier for improved linearity
D	An amplifier that uses drift-mode FETs for high efficiency

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It introduces transconductance to cancel the reactive part of impedance
B	It cancels the reactive part of the impedance and changes the resistive part to a desired value
C	Network resistances are substituted for load resistances and reactances are matched to the resistances
D	It introduces negative resistance to cancel the resistive part of impedance

33. - E7D12

What is the drop-out voltage of an analog voltage regulator?

Select	Answer
A	Minimum input-to-output voltage required to maintain regulation
B	Minimum input voltage for rated power dissipation
C	Maximum amount that the output voltage drops when the input voltage is varied over its specified range
D	Maximum amount that the output voltage may decrease at rated load

34. - E7E05

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

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

35. - E7F17

What do the letters I and Q in I/Q Modulation represent?

Select	Answer
A	Inactive and Quiescent
B	Instantaneous and Quasi-stable
C	In-phase and Quadrature
D	Instantaneous and Quenched

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	47
B	94
C	0.21
D	24

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Use of NP0 capacitors
B	Eliminating noise on the oscillator's power supply
C	Using the oscillator only for CW and digital signals
D	Mechanically isolating the oscillator circuitry from its enclosure

38. - E8A09

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

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

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It decreases as the RF carrier frequency increases
B	It does not depend on the RF carrier frequency
C	It varies with the square root of the RF carrier frequency
D	It increases as the RF carrier frequency increases

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It increases security
B	It facilitates error detection
C	It has more resolution than simple binary
D	It has more possible states than simple binary

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

Select	Answer
A	The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
B	If interference is detected by the receiver it will signal the transmitter to change frequencies
C	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
D	A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	8.15 dB
B	6.0 dB
C	3.85 dB
D	2.79 dB

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	3 dB
B	15 dB
C	24 dB
D	28 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 vertical angle increases
B	The front-to-back ratio decreases
C	The lobes align more in the direction of the wire
D	The lobes become more perpendicular to the wire

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

46. - 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 stub match
B	The omega match
C	The delta match
D	The gamma match

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	The same as the input impedance to the final generator stage
B	A capacitive reactance
C	The same as the characteristic impedance of the line
D	An inductive reactance

48. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Voltage circles and current arcs
B	Resistance circles and reactance arcs
C	Resistance lines and reactance chords
D	Voltage lines and current chords

49. - E9H09

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

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

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	Make sure signals from your station are less than the uncontrolled MPE limits
C	Advise your neighbors of the results of your tests
D	Make sure signals from your station are less than the controlled MPE limits

Figure E7-4

Figure E9-2