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	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
B	50 watts PEP effective radiated power relative to a dipole
C	50 watts PEP effective radiated power relative to an isotropic radiator
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 proposal must be submitted to the National Park Service
C	An Environmental Assessment must be submitted to the FCC
D	A form FSD-15 must be submitted to the Department of the Interior

3. - E1C06

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

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

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 located on the Earth's surface for communication with other Earth stations by means of Earth satellites
C	An amateur station located more than 50 km above the Earth's surface
D	An amateur station that transmits telemetry consisting of measurements of upper atmosphere

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and send the documents to the FCC according to instructions
B	They must collect and submit the documents to the coordinating VEC for grading
C	They must collect and send the documents to the NCVEC for grading
D	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	The equipment dealer assembled it from a kit
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
D	It was imported from a manufacturer in another country and was certificated by that country's government

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	An isotropic antenna
B	A circularly polarized antenna
C	A log-periodic dipole array
D	A linearly polarized antenna

8. - E2B16

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

Select	Answer
A	NTSC
B	Scottie
C	DRM
D	PAL

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

10. - E2D10

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

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
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. - E2E07

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

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

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Temperature inversion
B	The jet stream
C	Dust devil
D	Wind shear

13. - E3B05

Which amateur bands typically support long-path propagation?

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

14. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	Waning sunspot numbers
B	Very low solar activity
C	Moderate solar wind
D	An extreme geomagnetic storm

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	All of these choices are correct
B	Never use a high impedance probe to measure a low impedance circuit
C	Keep the signal ground connection of the probe as short as possible
D	Never use a DC-coupled probe to measure an AC circuit

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	Frequency order of the measurements
B	The relative time between measurements
C	Relative quality of the data
D	The port or ports at which measurements are made

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

Select	Answer
A	Anti-aliasing input filter bandwidth
B	CPU register width in bits
C	Analog-to-digital converter sample width in bits
D	RAM speed used for data storage

18. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

Select	Answer
A	A pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
B	A pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal
C	The receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
D	Signals less than 40 dBm will not generate audible third-order intermodulation products

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

Select	Answer
A	The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
B	The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
C	All of these choices are correct
D	The interfering signal may drift slowly across the HF spectrum

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	It has no effect on impedance matching
B	Matching bandwidth is decreased
C	Matching range is increased
D	Matching bandwidth is increased

21. - E5B03

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

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

22. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

Select	Answer
A	Faraday grid
B	Elliptical coordinates
C	Polar coordinates
D	Maidenhead grid

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	0.5
B	0.866
C	1.73
D	0.577

24. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

Select	Answer
A	Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
B	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
C	Only P-type semiconductor material can conduct current
D	Only N-type semiconductor material can conduct current

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Reverse voltage larger than the RF signal
B	A sub-harmonic pump signal
C	Capacitance of an RF coupling capacitor
D	Forward DC bias current

26. - E6C04

What is the primary advantage of tri-state logic?

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

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores confine most of the magnetic field within the core material
B	Toroidal cores have lower Q characteristics
C	Toroidal cores exhibit greater hysteresis
D	Toroidal cores make it easier to couple the magnetic energy into other components

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

29. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A device which measures the strength of a beam of light using analog to digital conversion
B	A device for generating RTTY signals by means of a rotating light source
C	A device which detects rotation of a control by interrupting a light source with a patterned wheel
D	A digital encryption device often used to encrypt spacecraft control signals

30. - E7A10

What is a truth table?

Select	Answer
A	A table of logic symbols that indicate the high logic states of an op-amp
B	A list of inputs and corresponding outputs for a digital device
C	A table of logic symbols that indicate the logic states of an op-amp
D	A diagram showing logic states when the digital device output is true

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 are relatively far in frequency from the desired signal
C	Because they maintain the sidebands, thus causing multiple duplicate signals
D	Because they are relatively close in frequency to the desired signal

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

Select	Answer
A	A network with only three discrete parts
B	A matching network in which all components are isolated from ground
C	A Phase Inverter Load network
D	A Pi-network with an additional series inductor on the output

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To cut down on waste heat generated by the power supply
B	To balance the low-voltage filament windings
C	To improve output voltage regulation
D	To boost the amount of output current

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a loop modulator followed by a mixer
B	By using a reactance modulator followed by a mixer
C	By using a balanced modulator followed by a filter
D	By driving a product detector with a DSB signal

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	A notch filter
B	A Hilbert-transform filter
C	An elliptical filter
D	An adaptive filter

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	28
B	7
C	14
D	0.07

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Negative feedback and balanced feedback
B	Armstrong and deForest
C	Pierce and Zener
D	Colpitts and Hartley

38. - E8A07

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

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

39. - E8B07

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

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

40. - E8C02

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

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

41. - E8D10

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

Select	Answer
A	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
B	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
C	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
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. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	9.85 dB
B	12.5 dB
C	6.17 dB
D	14.15 dB

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region of the ionosphere where radiated power is not refracted
B	The region where radiated power dissipates over a specified time period
C	The region where the shape of the antenna pattern is independent of distance
D	The region where radiated field strengths are obstructed by objects of reflection

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	Both the high-angle and low-angle radiation decrease
B	The low-angle radiation increases
C	The low-angle radiation decreases
D	The high-angle radiation increases

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
B	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
C	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
D	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The delta match
B	The gamma match
C	The epsilon match
D	The stub match

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	3.5 meters
B	0.2 meters
C	20 meters
D	2.3 meters

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Frequency
B	SWR
C	Points with constant resistance
D	Points with constant reactance

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It allows stations to communicate without giving away their position
B	It is electro statically balanced against ground, giving better nulls
C	It automatically cancels ignition noise in mobile installations
D	It eliminates tracking errors caused by strong out-of-band signals

50. - E0A08

What does SAR measure?

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

Figure E7-4