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

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	50 watts PEP effective radiated power relative to an isotropic radiator
B	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
C	50 watts PEP effective radiated power relative to a dipole
D	100 watts PEP effective radiated power relative to an isotropic radiator

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A letter of intent must be filed with the National Audubon Society
B	A form FSD-15 must be submitted to the Department of the Interior
C	An Environmental Assessment must be submitted to the FCC
D	A proposal must be submitted to the National Park Service

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under local control a control operator is not required to be present at a control point
B	Under automatic control there is no control operator
C	Under local control there is no control operator
D	Under automatic control the control operator is not required to be present at the control point

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
B	Any amateur station on the surface of the Earth
C	An amateur station that is not able to communicate using amateur satellites
D	An amateur station that transmits telemetry consisting of measurement of upper atmosphere

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
B	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
C	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
D	The prospective VE obtains accreditation from the FCC

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The polarization of uplink and downlink signals
B	The location of the ground control station
C	Power limits for uplink and downlink transmissions
D	The uplink and downlink frequency ranges

8. - E2B19

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

Select	Answer
A	None; they are allowed on all amateur frequencies
B	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
C	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
D	They are not permitted above 54 MHz

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

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	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
C	All of these choices are correct
D	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital

11. - E2E09

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

Select	Answer
A	MT63
B	RTTY
C	PSK31
D	PACTOR

12. - E3A15

What is an electromagnetic wave?

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

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Around sunrise
B	Around sunset
C	Early evening
D	Any time

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Vertical
B	Elliptical
C	Horizontal
D	Circular

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Network analyzer
B	Modulation monitor
C	Bit error rate tester
D	Logic analyzer

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	146.52 Hz
B	1465.20 Hz
C	146.52 kHz
D	10 Hz

17. - E4C10

Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?

Select	Answer
A	2400 Hz
B	6000 Hz
C	300 Hz
D	100 Hz

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Oscillator instability and severe audio distortion of all but the strongest received signals
B	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
C	Cross-modulation of the desired signal and desensitization from strong adjacent signals
D	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband

19. - E4E06

What is a major cause of atmospheric static?

Select	Answer
A	Thunderstorms
B	Geomagnetic storms
C	Solar radio frequency emissions
D	Meteor showers

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	31.4 kHz
B	218.3 kHz
C	436.6 kHz
D	15.7 kHz

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Current leads voltage by 90 degrees
B	Voltage and current are in phase
C	Voltage leads current by 90 degrees
D	Voltage and current are 180 degrees out of phase

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

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

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.577
C	1.73
D	0.5

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	Bipolar-type
B	Superconductor-type
C	P-type
D	N-type

25. - E6B07

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

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

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

Select	Answer
A	6
B	2
C	4
D	5

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Reactivity
B	Permeability
C	Thermal impedance
D	Resistance

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Axial lead
B	Radial lead
C	TO-220
D	Surface mount

29. - E6F12

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

Select	Answer
A	Holes
B	Electrons
C	Protons
D	Photons

30. - E7A03

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

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

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Increased overall intelligibility
B	Signal distortion and excessive bandwidth
C	Reduced intermodulation products
D	Signal inversion

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	Pi-networks are designed for balanced input and output
B	L-networks cannot perform impedance transformation
C	Pi-networks have fewer components
D	The Q of Pi-networks can be varied depending on the component values chosen

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To allow for remote control of the power supply
B	To provide a dual-voltage output for reduced power applications
C	To allow the filter capacitors to charge gradually
D	To compensate for variations of the incoming line voltage

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

Select	Answer
A	A circuit for filtering two closely adjacent signals
B	An automatic band-switching circuit
C	A circuit for detecting FM signals
D	An FM generator circuit

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	6 bits
B	4 bits
C	10 bits
D	8 bits

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

Select	Answer
A	76
B	1
C	38
D	0.03

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Taft, Pierce and negative feedback
B	Taft, Hartley and Pierce
C	Colpitts, Hartley and Pierce
D	Pierce, Fenner and Beane

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	8
C	256
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 increases as the RF carrier frequency increases
D	It varies with the square root of the RF carrier frequency

40. - E8C06

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

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

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	Strong ALC action
B	Rapid signal fading
C	High reflected power
D	Harmonics on higher bands

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The combined losses of the antenna elements and feed line
B	The specific impedance of the antenna
C	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
D	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal

43. - E9B02

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

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

44. - E9C05

What is an OCFD antenna?

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

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth decreases
B	SWR bandwidth increases
C	More common-mode current is present on the feed line
D	Gain is reduced

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	A series capacitor
B	A shunt inductor
C	Pi-L-network
D	Pi-network

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	20 meters
B	71 meters
C	10 meters
D	15 meters

48. - E9G03

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

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

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	All of these choices are correct
B	Low loss coax transmission line is essential for good performance
C	They must be erected at least 1/2 wavelength above the ground to attain good directivity
D	Atmospheric noise is so high that gain over a dipole is not important

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Hearing loss caused by high voltage corona discharge
B	Ingestion of ozone gas from the cooling system
C	Blood clotting from the intense magnetic field
D	Localized heating of the body from RF exposure in excess of the MPE limits

Figure E6-5

Figure E7-4

Figure E9-1