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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	Yes, because the displayed frequency is within the 20 meter band
B	No, the sideband will extend beyond the band edge
C	Yes, because you were not the station calling CQ
D	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
B	A signal transmitted to prevent its detection by any station other than the intended recipient
C	An amateur station transmission made at random without the proper call sign identification
D	Any transmitted signal that unintentionally interferes with another licensed radio station

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	When agreed upon by the sending or receiving station
B	Only when transmitting RTTY or data emissions
C	When approved by the National Telecommunication and Information Administration
D	Never

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	6 meters and 2 meters
B	6 meters, 2 meters, and 1.25 meters
C	2 meters
D	2 meters and 1.25 meters

5. - E1E04

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

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

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

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geostationary
B	LEO
C	HEO
D	Geomagnetic

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Specific tone amplitudes
B	Elapsed time
C	Specific tone frequencies
D	A two-tone signal

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

10. - E2D10

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

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

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	First Error Correction
B	Final Error Correction
C	Fatal Error Correction
D	Forward Error Correction

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	1.8 MHz - 1.9 MHz
B	10 MHz - 14 MHz
C	28 MHz - 148 MHz
D	220 MHz - 450 MHz

13. - E3B11

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

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

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Sporadic-E
B	Polar paths
C	NVIS
D	Transequatorial propagation

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	Match the antenna to the load
B	Attenuate the transmitter output going to the spectrum analyzer
C	All of these choices are correct
D	Use high quality double shielded coaxial cables to reduce signal losses

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1.4652 kHz
B	0.1 MHz
C	1.4652 Hz
D	14.652 Hz

17. - E4C13

How does a narrow-band roofing filter affect receiver performance?

Select	Answer
A	It improves sensitivity by reducing front end noise
B	It improves dynamic range by attenuating strong signals near the receive frequency
C	It improves intelligibility by using low Q circuitry to reduce ringing
D	All of these choices are correct

18. - E4D13

Which of the following can cause receiver desensitization?

Select	Answer
A	Audio bias adjusted too high
B	Audio gain adjusted too low
C	Strong adjacent channel signals
D	Squelch gain misadjusted

19. - E4E05

How can noise from an electric motor be suppressed?

Select	Answer
A	By installing a bypass capacitor in series with the motor leads
B	By installing a high pass filter in series with the motor's power leads
C	By installing a brute-force AC-line filter in series with the motor leads
D	By using a ground-fault current interrupter in the circuit used to power the motor

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

Select	Answer
A	Approximately equal to circuit resistance
B	Approximately equal to inductive reactance
C	Approximately equal to capacitive reactance
D	High, as compared to the circuit resistance

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	55 seconds
B	440 seconds
C	110 seconds
D	220 seconds

22. - E5C12

If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?

Select	Answer
A	It contains resistance and inductive reactance
B	It contains resistance and capacitive reactance
C	It has to be a direct current circuit
D	It is equivalent to a pure resistance

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

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
B	To provide a voltage reference for the correct amount of reverse-bias gate voltage
C	To keep the gate voltage within specifications and prevent the device from overheating
D	To protect the substrate from excessive voltages

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a constant voltage source
B	As a high voltage rectifier
C	As an RF detector
D	As a constant current source

26. - E6C04

What is the primary advantage of tri-state logic?

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

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

Select	Answer
A	Polystyrene and polyethylene
B	Teflon and Delrin
C	Ferrite and brass
D	Cobalt and aluminum

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Gallium nitride
B	Silicon nitride
C	Silicon
D	Silicon dioxide

29. - E6F07

What is a solid state relay?

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

30. - E7A11

What type of logic defines "1" as a high voltage?

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

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	Low bandwidth
B	Low input impedance
C	High power gain
D	High filament voltage

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

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A varactor diode
B	A tunnel diode
C	A Zener diode
D	An SCR

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	The sum, difference and square root of the input frequencies
B	The two input frequencies along with their sum and difference frequencies
C	1.414 and 0.707 times the input frequency
D	Two and four times the original frequency

35. - E7F03

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

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

36. - E7G03

What is the typical input impedance of an integrated circuit op-amp?

Select	Answer
A	100 ohms
B	Very high
C	1000 ohms
D	Very low

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit also known as a monostable multivibrator
B	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
C	An electronic circuit consisting of a precision push-pull amplifier with a differential input
D	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	1 to 1
B	100 to 1
C	25 to 1
D	2.5 to 1

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A bandwidth compression technique using Fourier transforms
B	A frequency modulation technique which uses non-harmonically related frequencies
C	A digital mode for narrow band, slow speed transmissions
D	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

40. - E8C06

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

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	Signals not using the spread spectrum algorithm are suppressed in the receiver
B	If interference is detected by the receiver it will signal the transmitter to change frequencies
C	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
D	The receiver is always equipped with a digital blanker

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. - 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	15 dB
D	28 dB

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The horizontal beam width increases with height
B	The main lobe takeoff angle increases with increasing height
C	The main lobe takeoff angle decreases with increasing height
D	The horizontal beam width decreases with height

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Improved radiation efficiency
B	Lower Q
C	Greater structural strength
D	Higher losses

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	Pi-network
C	Pi-L-network
D	A shunt inductor

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	The surge impedance is higher in a parallel feed line
B	Skin effect is less pronounced in the coaxial cable
C	The characteristic impedance is higher in a parallel feed line
D	Electrical signals move more slowly in a coaxial cable than in air

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Reactance axis
B	Impedance axis
C	Polar axis
D	Prime axis

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 automatically cancels ignition noise in mobile installations
C	It is electro statically balanced against ground, giving better nulls
D	It eliminates tracking errors caused by strong out-of-band signals

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

Select	Answer
A	The high gain antennas commonly used can result in high exposure levels
B	Microwaves often travel long distances by ionospheric reflection
C	Microwaves are ionizing radiation
D	The extremely high frequency energy can damage the joints of antenna structures

Figure E9-2

Figure E9-3