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

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	1.0
B	3.0
C	2.0
D	0.5

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	All of these choices are correct
C	Messages intended for connection to users of the maritime satellite service
D	Business-related messages for non-profit organizations

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	70 cm and 33 cm
B	70 cm and 13 cm
C	70 cm only
D	33 cm and 13 cm

5. - E1E12

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

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

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

7. - E2A06

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

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

8. - E2B16

Which is a video standard used by North American Fast Scan ATV stations?

Select	Answer
A	PAL
B	Scottie
C	DRM
D	NTSC

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send your full call sign and grid square
B	Send only the last two letters of your call sign until you make contact
C	Send the call sign of the DX station three times, the words "this is", then your call sign three times
D	Send your full call sign once or twice

10. - E2D10

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

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

11. - E2E07

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

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

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is at apogee
B	When the Moon is at perigee
C	When the MUF is above 30 MHz
D	When the Moon is full

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Signals reflected back toward the transmitting station
B	Successive ionospheric reflections without an intermediate reflection from the ground
C	Propagation away from the great circle bearing between stations
D	Propagation across the geomagnetic equator

14. - E3C10

What does the 304A solar parameter measure?

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

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It prevents oscillation in a low-frequency counter circuit
B	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
C	It amplifies low level signals for more accurate counting
D	It divides a higher frequency signal so a low-frequency counter can display the input frequency

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	Intermodulation distortion occurs
B	Harmonics are generated
C	A less accurate reading results
D	Cross modulation occurs

17. - E4C05

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

Select	Answer
A	The minimum detectable signal as a function of receive frequency
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 noise figure of a 1 Hz bandwidth receiver

18. - E4D09

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

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

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	Harmonics of the AC power line frequency
B	A common-mode signal at the frequency of the radio transmitter
C	An electrical-sparking signal
D	A differential-mode signal at the AC power line frequency

20. - E5A10

How is the Q of an RLC series resonant circuit calculated?

Select	Answer
A	Resistance divided by the reactance of either the inductance or capacitance
B	Reactance of either the inductance or capacitance divided by the resistance
C	Reactance of either the inductance or capacitance times the resistance
D	Reactance of the inductance times the reactance of the capacitance

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	14 degrees with the voltage leading the current
B	14 degrees with the voltage lagging the current
C	76 degrees with the voltage lagging the current
D	76 degrees with the voltage leading the current

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	The difference between the resistive and reactive components
B	Reactive component
C	Resistive component
D	The sum of the reactive and resistive components

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as heat in the circuit
B	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
C	It is dissipated as kinetic energy in the circuit
D	It is dissipated in the formation of inductive and capacitive fields

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	2
B	1
C	3
D	6

25. - E6B07

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

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

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	The input switching threshold is about two times the power supply voltage
B	The input switching threshold is about one-half the power supply voltage
C	Input signals are stronger
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D05

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

Select	Answer
A	Ferrite toroids generally have better temperature stability
B	Ferrite toroids generally have lower initial permeability
C	Ferrite toroids are easier to use with surface mount technology
D	Ferrite toroids generally require fewer turns to produce a given inductance value

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	Through a resistor and/or RF choke connected to the amplifier output lead
D	MMICs require no operating bias

29. - E6F14

Which of the following is true of LCD displays?

Select	Answer
A	All of these choices are correct
B	They may be hard view through polarized lenses
C	They only display alphanumeric symbols
D	They are hard to view in high ambient light conditions

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It produces ten output pulses for every input pulse
B	It adds two decimal numbers together
C	It decodes a decimal number for display on a seven segment LED display
D	It produces one output pulse for every ten input pulses

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they invert the sidebands causing distortion
B	Because they maintain the sidebands, thus causing multiple duplicate signals
C	Because they are relatively close in frequency to the desired signal
D	Because they are relatively far in frequency from the desired signal

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	A band-pass filter
B	A Pi-network filter
C	An all-pass filter
D	A notch filter

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

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

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce PM signals by using an electrically variable resistance
B	To produce PM signals by using an electrically variable inductance or capacitance
C	To produce AM signals by using an electrically variable inductance or capacitance
D	To produce AM signals by using an electrically variable resistance

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters can respond faster to impulses
B	FIR filters delay all frequency components of the signal by the same amount
C	FIR filters are easier to implement for a given set of passband rolloff requirements
D	All of these choices are correct

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	An echo caused by a long time delay
B	Undesired oscillations added to the desired signal
C	Partial cancellation of the signal over a range of frequencies
D	A reduction in high frequency response

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 diode-switching matrix synthesizer
C	A direct digital synthesizer
D	A phase locked loop synthesizer

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The characteristics of the modulating signal
B	The frequency of the modulating signal
C	The amplifier gain
D	The degree of carrier suppression

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more signals are arranged to share discrete time slots of a data transmission
B	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
C	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
D	Two or more signals are quadrature modulated to increase bandwidth efficiency

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The number of control characters in a message packet
B	The number of characters carried per second by the station-to-station link
C	The rate at which the waveform of a transmitted signal changes to convey information
D	The duration of each bit in a message sent over the air

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It includes built in error correction features
B	It uses one character as a shift code to send numeric and special characters
C	It is possible to transmit both upper and lower case text
D	It contains fewer information bits per character than any other code

42. - E9A18

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Power factor
B	Apparent power
C	Effective radiated power
D	Half-power bandwidth

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

Select	Answer
A	Draw two imaginary lines through the ends of the elements and measure the angle between the lines
B	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
C	Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference
D	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna

44. - E9C05

What is an OCFD antenna?

Select	Answer
A	A multiband dipole antenna using one-way circular polarization for frequency diversity
B	A dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
C	An eight band dipole antenna using octophase filters
D	A remotely tunable dipole antenna using orthogonally controlled frequency diversity

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	It is increased
B	It becomes flat
C	No change occurs
D	It is decreased

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The gamma matching system
B	The omega matching system
C	The stub matching system
D	The delta matching system

47. - E9F13

What impedance does a 1/4 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 transmission line
B	Very high impedance
C	Very low impedance
D	The same as the generator output impedance

48. - E9G02

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

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

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

50. - E0A08

What does SAR measure?

Select	Answer
A	The rate at which RF energy is absorbed by the body
B	Synthetic Aperture Ratio of the human body
C	Signal Amplification Rating
D	The rate of RF energy reflected from stationary terrain

Figure E6-2