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	Any FCC-issued amateur license
C	Only General class or higher amateur licenses
D	An unrestricted Radiotelephone Operator Permit

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	A signal transmitted to prevent its detection by any station other than the intended recipient
B	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
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. - E1C07

What is meant by local control?

Select	Answer
A	Automatically manipulating local station controls
B	Controlling a station through a local auxiliary link
C	Direct manipulation of the transmitter by a control operator
D	Controlling a repeater using a portable handheld transceiver

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
B	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
C	The space station must cease all transmissions after 5 years
D	All of these choices are correct

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	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 prospective VE obtains accreditation from the FCC

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	The equipment dealer assembled it from a kit
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. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	Whether the satellite is in a polar or equatorial orbit
B	The satellite's uplink and downlink frequency bands
C	The type of signals that can be relayed through the satellite
D	The satellite's orientation with respect to the Earth

8. - E2B14

What aspect of an amateur slow-scan television signal encodes the brightness of the picture?

Select	Answer
A	Sync frequency
B	Sync amplitude
C	Tone amplitude
D	Tone frequency

9. - E2C07

What is the Cabrillo format?

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

10. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	All of these choices are correct
B	15 second timed transmission sequences with stations alternating based on location
C	Use of high speed CW or digital modes
D	Short transmission with rapidly repeated call signs and signal reports

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Audio FSK can be performed anywhere in the transmit chain
B	Direct FSK applies the data signal to the transmitter VFO
C	Direct FSK uses a DC-coupled data connection
D	Audio FSK has a superior frequency response

12. - E3A15

What is an electromagnetic wave?

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

13. - E3B03

What is the best time of day for transequatorial propagation?

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

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It peaks at roughly 14 MHz
B	It stays the same
C	It decreases
D	It increases

15. - E4A04

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

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

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	1465.20 Hz
B	146.52 Hz
C	146.52 kHz
D	10 Hz

17. - E4C04

How is the noise figure of a receiver defined?

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

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	The third-order product of two signals which are in the band of interest is also likely to be within the band
B	Third-order products are an indication of poor image rejection
C	Third-order intermodulation produces three products for every input signal within the band of interest
D	The third-order intercept is much higher than other orders

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	Received audio in the speech range might have an echo effect
B	The audio frequency bandwidth of the received signal might be compressed
C	FM signals can no longer be demodulated
D	Nearby signals may appear to be excessively wide even if they meet emission standards

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Internal voltages and circulating currents increase
B	Phase shift can become uncontrolled
C	Fewer components are needed for the same performance
D	Parasitic effects are minimized

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	A discharge factor of one
B	One discharge period
C	An exponential discharge rate of one
D	One time constant

22. - E5C13

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

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

23. - E5D01

What is the result of skin effect?

Select	Answer
A	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
B	Thermal effects on the surface of the conductor increase the impedance
C	Thermal effects on the surface of the conductor decrease the impedance
D	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	They are both low impedance
B	An FET has low input impedance; a bipolar transistor has high input impedance
C	They are both high impedance
D	An FET has high input impedance; a bipolar transistor has low input impedance

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Junction
B	Zener
C	Tunnel
D	Point contact

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

27. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	Inter-turn capacitance
B	Inductive kickback
C	The skin effect
D	Non-linear core hysteresis

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Two chips in each package (Dual In Package)
B	Low leakage doubly insulated package
C	Package mounts in a direct inverted position
D	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)

29. - E6F05

Which describes an optical shaft encoder?

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

30. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic "0" at its output if some but not all inputs are logic "1"
B	It produces logic "1" at its output only when all inputs are logic "1"
C	It produces logic "0" at its output only when all inputs are logic "1"
D	It produces logic "0" at its output only when all inputs are logic "0"

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

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. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	The conduction of a control element is varied to maintain a constant output voltage
B	It has a ramp voltage as its output
C	The control element duty cycle is proportional to the line or load conditions
D	It eliminates the need for a pass transistor

34. - E7E10

How does a diode detector function?

Select	Answer
A	By mixing signals with noise in the transition region of the diode
B	By rectification and filtering of RF signals
C	By sensing the change of reactance in the diode with respect to frequency
D	By breakdown of the Zener voltage

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

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
B	The differential input voltage needed to bring the open loop output voltage to zero
C	The output voltage of the op-amp minus its input voltage
D	The potential between the amplifier input terminals of the op-amp in an open loop condition

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	NP0 capacitors
B	Wirewound resistors
C	Toroidal inductors
D	Non-inductive resistors

38. - E8A04

What is "dither" with respect to analog to digital converters?

Select	Answer
A	A method of decimation by randomly skipping samples
B	A small amount of noise added to the input signal to allow more precise representation of a signal over time
C	An abnormal condition where the converter cannot settle on a value to represent the signal
D	An error caused by irregular quantization step size

39. - E8B11

What is digital time division multiplexing?

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

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By transmitting extra data that may be used to detect and correct transmission errors
B	By varying the frequency shift of the transmitted signal according to a predefined algorithm
C	By transmitting a special algorithm to the receiving station along with the data characters
D	By the receiving station repeating each block of three data characters

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth
B	The signal can overpower interfering signals
C	Faster transmission rate
D	Foreign language characters can be sent

42. - E9A16

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	300 watts
B	317 watts
C	2000 watts
D	126 watts

43. - E9B09

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

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

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It reduces losses in the radiating portion of the antenna
B	It changes the impedance angle of the matching network
C	It causes increased SWR
D	It reduces low-angle radiation

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

Select	Answer
A	It radiates the harmonics and fundamental equally well
B	It might radiate harmonics
C	It is too sharply directional at lower frequencies
D	It must be neutralized

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	A reflection coefficient greater than 1
B	A dielectric constant greater than 1
C	An SWR less than 1:1
D	An SWR greater than 1:1

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

Select	Answer
A	The center conductor resistivity
B	The termination impedance
C	The line length
D	Dielectric materials used in the line

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

Select	Answer
A	In fractions of antenna electrical frequency
B	In fractions of transmission line electrical frequency
C	In fractions of transmission line electrical wavelength
D	In fractions of antenna electrical wavelength

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	They must be erected at least 1/2 wavelength above the ground to attain good directivity
C	Atmospheric noise is so high that gain over a dipole is not important
D	Low loss coax transmission line is essential for good performance

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Mica
B	Uranium Hexafluoride
C	Beryllium Oxide
D	Zinc oxide