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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	Yes, the displayed frequency is within the 80 meter CW band segment
B	Yes, the DX station initiated the contact
C	No, one of the sidebands of the CW signal will be out of the band
D	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz

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	2.0
C	3.0
D	0.5

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	5 minutes
B	10 minutes
C	3 minutes
D	30 seconds

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station that is not able to communicate using amateur satellites
B	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
C	Any amateur station on the surface of the Earth
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 procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
B	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
C	The prospective VE obtains accreditation from the FCC
D	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted

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. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The time it takes for a satellite to travel from perigee to apogee
B	The point of minimum height of a satellite's orbit
C	The time it takes for a satellite to complete one revolution around the Earth
D	The point of maximum height of a satellite's orbit

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

Select	Answer
A	All of these choices are correct
B	Frequency modulation of the video carrier
C	Frequency-modulated sub-carrier
D	A separate VHF or UHF audio link

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A method of exchanging information during a contest QSO
B	The most common set of contest rules
C	The rules of order for meetings between contest sponsors
D	A standard for submission of electronic contest logs

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	APRS
B	FSK441
C	Hellschreiber
D	WSPR

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	Local
B	Automatic
C	ALE can use any type of control
D	Remote

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	100 miles to 300 miles
B	1200 miles
C	10 miles to 50 miles
D	2500 miles

13. - E3B03

What is the best time of day for transequatorial propagation?

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

14. - E3C08

What does the space weather term G5 mean?

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

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Q of the interface of the interface circuit
B	All of these choices are correct
C	Analog-to-digital conversion speed of the soundcard
D	Amount of memory on the soundcard

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	14.652 kHz
B	165.2 Hz
C	1.4652 MHz
D	146.52 Hz

17. - E4C04

How is the noise figure of a receiver defined?

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

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. - E4E06

What is a major cause of atmospheric static?

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

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	44.72 MHz
B	1.78 MHz
C	3.56 MHz
D	22.36 MHz

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	It is shifted by 90 degrees
D	The sign is reversed

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

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

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The amount of current flowing through the conductor
B	The ratio of the current to the resistance
C	The diameter of the conductor
D	The resistance divided by the current

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free protons
B	Free electrons
C	Free neutrons
D	Holes

25. - E6B08

Which of the following describes a type of semiconductor diode?

Select	Answer
A	Thermionic emission diode
B	Electrolytic rectifier
C	CMOS-field effect
D	Metal-semiconductor junction

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	Programmable equipment used for testing digital logic integrated circuits
B	A device to control industrial equipment
C	A programmable collection of logic gates and circuits in a single integrated circuit
D	An algorithm for simulating logic functions during circuit design

27. - E6D02

What is the equivalent circuit of a quartz crystal?

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

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Nearly infinite gain, very high input impedance, and very low output impedance
B	Plate current that is controlled by a control grid
C	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
D	The ability to retrieve information from a single signal even in the presence of other strong signals

29. - E6F07

What is a solid state relay?

Select	Answer
A	A relay using transistors to drive the relay coil
B	A device that uses semiconductors to implement the functions of an electromechanical relay
C	A passive delay line
D	A mechanical relay that latches in the on or off state each time it is pulsed

30. - E7A12

What type of logic defines "0" as a high voltage?

Select	Answer
A	Positive Logic
B	Reverse Logic
C	Assertive Logic
D	Negative logic

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	Neutralization
B	Use a resistor in series with the emitter
C	Select transistors with high beta
D	All of these choices are correct

32. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Select	Answer
A	Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
B	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
C	An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
D	A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

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

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	An FM generator circuit
D	A circuit for detecting FM signals

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

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	As an audio filter in a receiver
B	As a high-pass filter used to block RFI at the input to receivers
C	As a low-pass filter used between a transmitter and a transmission line
D	For smoothing power supply output

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Provide the crystal with a specified parallel inductance
B	Provide the crystal with a specified parallel capacitance
C	Bias the crystal at a specified current
D	Bias the crystal at a specified voltage

38. - E8A07

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

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

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Percentage of modulation
B	Quieting index
C	Modulation index
D	FM compressibility

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Extended Binary Coded Decimal Interchange Code
C	Excess 3 code
D	Gray code

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	Harmonics on higher bands
C	Rapid signal fading
D	High reflected power

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(total resistance / radiation resistance) x 100 per cent
B	(effective radiated power / transmitter output) x 100 percent
C	(radiation resistance / total resistance) x 100 per cent
D	(radiation resistance / transmission resistance) x 100 per cent

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Mutual impedance analysis
B	Graphical analysis
C	Calculus differentiation with respect to physical properties
D	Method of Moments

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It decreases the ground loss
B	It reflects the standing waves on the antenna elements back to the transmitter
C	It changes the radiation pattern from bidirectional to unidirectional
D	It changes the radiation pattern from horizontal to vertical polarization

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

Select	Answer
A	To maximize losses
B	To minimize the Q
C	To minimize losses
D	To swamp out harmonics

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It allows single-band antennas to operate on other bands
B	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
C	It ensures that each driven element operates in concert with the others to create the desired antenna pattern
D	It makes sure the antenna has a low-angle radiation pattern

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

Select	Answer
A	Standing wave ratio
B	Surge impedance
C	Characteristic impedance
D	Velocity factor

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing either the number of wire turns in the loop or the area of the loop structure or both
B	By increasing the number of wire turns in the loop and reducing the area of the loop structure
C	By reducing the permeability of the loop shield
D	By winding adjacent turns in opposing directions

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

Select	Answer
A	Use an antenna modeling program to calculate field strength at accessible locations
B	All of the choices are correct
C	Use a hand calculator plus Smith-chart equations to calculate the fields
D	Use a calibrated antenna analyzer