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

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1. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

Select	Answer
A	An unrestricted Radiotelephone Operator Permit
B	Any FCC-issued amateur license
C	Any amateur license with an FCC Marine or Aircraft endorsement
D	Only General class or higher amateur licenses

2. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must cease operation on all frequencies above 30 MHz
B	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference
C	The amateur station must cease operation on all frequencies below 30 MHz
D	The amateur station must cease operation

3. - E1C04

What is meant by IARP?

Select	Answer
A	The internal amateur radio practices policy of the FCC
B	A forecast of intermittent aurora radio propagation
C	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
D	An indication of increased antenna reflected power

4. - E1D03

What is a telecommand station in the amateur satellite service?

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

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 77%
B	Minimum passing score of 74%
C	Minimum passing score of 80%
D	Minimum passing score of 70%

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must exhibit a gain of 0 dB or less over its full output range
B	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
C	It must produce full legal output when driven by not more than 5 watts of mean RF input power
D	It must be capable of external RF switching between its input and output networks

7. - E2A14

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

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

8. - E2B01

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

Select	Answer
A	60
B	90
C	30
D	120

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
B	To separate the calling stations from the DX station
C	All of these choices are correct
D	To improve operating efficiency by reducing interference

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To delay download of telemetry between satellites
B	To relay messages between satellites
C	To store digital messages in the satellite for later download by other stations
D	To upload operational software for the transponder

11. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	PACTOR
B	RTTY
C	Hellschreiber
D	AMTOR

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The E layer
B	The D layer
C	The F1 layer
D	The F2 layer

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Late at night
B	Afternoon or early evening
C	Noon
D	Morning

14. - E3C10

What does the 304A solar parameter measure?

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

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

Select	Answer
A	It can directly measure the modulation index of an FM transmitter
B	It does not require an expensive high-precision time base
C	It provides improved resolution of low-frequency signals within a comparable time period
D	It can run on battery power for remote measurements

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
B	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
C	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
D	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio of thermal noise to atmospheric noise
B	The ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network
C	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise
D	The ratio of atmospheric noise to phase noise

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	146.34 MHz and 146.61 MHz
B	146.10 MHz and 147.30 MHz
C	146.88 MHz and 146.34 MHz
D	173.35 MHz and 139.40 MHz

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

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

Select	Answer
A	Resonance
B	Capacitance
C	Conductance
D	Resistance

21. - E5B12

What is admittance?

Select	Answer
A	The turns ratio of a transformer
B	The term for the gain of a field effect transistor
C	The inverse of impedance
D	The unit used for Q factor

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By real and imaginary parts
B	By phase angle and amplitude
C	By X and R values
D	By Y and G values

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

24. - E6A05

What is the alpha of a bipolar junction transistor?

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

25. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Charge carrier depletion
B	Excessive junction temperature
C	Excessive inverse voltage
D	Insufficient forward voltage

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	High speed operation
B	More efficient arithmetic operations
C	Ability to connect many device outputs to a common bus
D	Low power consumption

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
C	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
D	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance

28. - E6E01

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

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

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Electrons
B	Holes
C	Protons
D	Photons

30. - E7A01

Which is a bi-stable circuit?

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

31. - E7B01

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

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

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Extremely flat response over its pass band with gradually rounded stop band corners
B	Gradual passband rolloff with minimal stop band ripple
C	Extremely sharp cutoff with one or more notches in the stop band
D	Gradual passband rolloff with extreme stop band ripple

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	The resistance of a control element is varied in direct proportion to the line voltage or load current
B	It gives a ramp voltage at its output
C	It is generally less efficient than a linear regulator
D	The controlled device's duty cycle is changed to produce a constant average output voltage

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The frequency components present in the modulating signal
B	The unmodulated bandwidth of the transmitted signal
C	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
D	The lowest frequency band that the transmitter or receiver covers

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	10 bits
B	6 bits
C	4 bits
D	8 bits

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A RF amplifier used in the UHF and microwave regions
B	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
C	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
D	A digital audio amplifier whose characteristics are determined by components external to the amplifier

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

Select	Answer
A	Through a tapped coil
B	Through a capacitive divider
C	Through a neutralizing capacitor
D	Through link coupling

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A cosine wave
B	A sine wave
C	A sawtooth wave
D	A square wave

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	OFDM signals are not allowed on amateur bands
B	EME
C	High speed digital modes
D	Extremely low-power contacts

40. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	1.0 kHz
B	0.1 Hz
C	0.3 kHz
D	0.5 kHz

41. - E8D10

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

Select	Answer
A	Baudot uses 7 data bits per character, ASCII uses 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 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
D	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

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	The standing wave ratio
B	Soil conductivity
C	Take-off angle
D	Distance from the transmitter

43. - E9B15

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

Select	Answer
A	3 dB
B	24 dB
C	28 dB
D	15 dB

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band trap antenna
B	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
C	A phased array antenna consisting of multiple loops
D	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

Select	Answer
A	It radiates the harmonics and fundamental equally well
B	It might radiate harmonics
C	It must be neutralized
D	It is too sharply directional at lower frequencies

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To provide a rejection notch that prevents the radiation of harmonics
B	To provide DC isolation between the feed line and the antenna
C	To transform the antenna impedance to a higher value
D	To cancel the inductive reactance of the matching network

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

48. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Satellite azimuth and elevation bearings
B	Beam headings and radiation patterns
C	Trigonometric functions
D	Impedance and SWR values in transmission lines

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	A fixed receiving station plots three headings to the signal source
B	A fixed receiving station uses three different antennas to plot the location of the signal source
C	Antenna headings from several different receiving locations are used to locate the signal source
D	The geometric angles of sky waves from the source are used to determine its position

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	Beryllium Oxide
B	Zinc oxide
C	Uranium Hexafluoride
D	Mica

Figure E9-2