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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	The exact upper band edge
B	300 Hz below the upper band edge
C	3 kHz below the upper band edge
D	1 kHz below the upper band edge

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	1 mile
C	30 miles
D	3 miles

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	Business-related messages for non-profit organizations
C	All of these choices are correct
D	Messages intended for connection to users of the maritime satellite service

4. - E1D08

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

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

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

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

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	APRS
B	Radar
C	Bandwidth compressed LORAN
D	Doppler shift of beacon signals

8. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	120
B	30
C	60
D	90

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Repeater contacts between U.S. club members
B	Contacts using tactical call signs
C	Special event contacts between stations in the U.S.
D	Contacts between a U.S. station and a non-U.S. station

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Digipeating
B	Multi-satellite relaying
C	Node hopping
D	Store-and-forward

11. - E2E11

What is the difference between direct FSK and audio FSK?

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

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

Select	Answer
A	Gray-line
B	Lightning discharges
C	Warm and cold fronts
D	Sprites and jets

13. - E3B08

What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?

Select	Answer
A	Sporadic-E
B	Long-path
C	Transequatorial
D	Gray-line

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	A meteor ping
B	A solar flare has occurred
C	Long-path propagation is occurring
D	Increased transequatorial propagation likely

15. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	Antenna analyzers automatically tune your antenna for resonance
B	Antenna analyzers do not need an external RF source
C	All of these choices are correct
D	Antenna analyzers display a time-varying representation of the modulation envelope

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

Select	Answer
A	Short circuit, open circuit, and resonant circuit
B	Short circuit, open circuit, and 50 ohms
C	50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
D	50 ohms, 75 ohms, and 90 ohms

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

Select	Answer
A	15.210 MHz
B	13.845 MHz
C	14.445 MHz
D	14.755 MHz

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Increase the receiver front end gain
B	Decrease the RF bandwidth of the receiver
C	Switch from fast AGC to slow AGC
D	Raise the receiver IF frequency

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Ignition noise
B	All of these choices are correct
C	Power line noise
D	Broadband white noise

20. - E5A17

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

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

21. - E5B12

What is admittance?

Select	Answer
A	The term for the gain of a field effect transistor
B	The unit used for Q factor
C	The turns ratio of a transformer
D	The inverse of impedance

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	Elliptical coordinates
C	Maidenhead grid
D	Rectangular coordinates

23. - E5D03

What is microstrip?

Select	Answer
A	Miniature coax used for low power applications
B	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
C	Lightweight transmission line made of common zip cord
D	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies

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	Only N-type semiconductor material can conduct current
C	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
D	Only P-type semiconductor material can conduct current

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Forward bias
B	Zero bias
C	Reverse bias
D	Inductive bias

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	Many similar gates are less expensive than a mixture of gate types
B	Complex logic functions can be created in a single integrated circuit
C	All of these choices are correct
D	A PGA contains its own internal power supply

27. - E6D02

What is the equivalent circuit of a quartz crystal?

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

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Point-to-point construction
B	Ground-plane construction
C	Microstrip construction
D	Wave-soldering construction

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 relay using transistors to drive the relay coil
C	A passive delay line
D	A mechanical relay that latches in the on or off state each time it is pulsed

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 "0"
D	It produces logic "0" at its output only when all inputs are logic "1"

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Fixed bias
B	Self bias
C	Output load resistor
D	Emitter bypass

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The amplitude of the signals passing through the filter
B	The relative frequencies of the individual crystals
C	The gain of the RF stage preceding the filter
D	The DC voltage applied to the quartz crystal

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

Select	Answer
A	It provides negative feedback to improve regulation
B	It provides a constant load for the voltage source
C	It provides D1 with current
D	It increases the current-handling capability of the regulator

34. - E7E08

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

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

35. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	Combine signals with a quadrature phase relationship
B	Mixing products are converted to voltages and subtracted by adder circuits
C	A frequency synthesizer removes the unwanted sidebands
D	Emulation of quartz crystal filter characteristics

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A RF amplifier used in the UHF and microwave regions
B	A digital audio amplifier whose characteristics are determined by components external to the amplifier
C	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
D	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

Select	Answer
A	Through link coupling
B	Through a capacitive divider
C	Through a neutralizing capacitor
D	Through a tapped coil

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Level shifting
B	Phase reversal
C	Sequential sampling
D	Harmonic regeneration

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	Quieting index
B	Percentage of modulation
C	Modulation index
D	FM compressibility

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Reed-Solomon character encoding
B	Use of sinusoidal data pulses
C	Zero-sum character encoding
D	Use of trapezoidal data pulses

41. - E8D12

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

Select	Answer
A	Faster transmission rate
B	Foreign language characters can be sent
C	The signal can overpower interfering signals
D	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

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Reduce the diameter of the radiating element
B	Shorten the radiating element
C	Isolate the coax shield from ground
D	Install a good radial system

43. - E9B09

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

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

44. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

Select	Answer
A	The horizontal beam width increases in the uphill direction
B	The main lobe takeoff angle decreases in the downhill direction
C	The horizontal beam width decreases in the downhill direction
D	The main lobe takeoff angle increases in the downhill direction

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
B	An electrically short connection to a metal water pipe
C	A 50 ohm resistor connected to ground
D	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Reflection coefficient
B	Characteristic impedance
C	Dielectric constant
D	Velocity factor

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	The same as the characteristic impedance of the transmission line
B	The same as the generator output impedance
C	Very high impedance
D	Very low impedance

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Smith chart
B	Free space radiation directivity chart
C	Elevation angle radiation pattern chart
D	Azimuth angle radiation pattern chart

49. - E9H10

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

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

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	Localized heating of the body from RF exposure in excess of the MPE limits
D	Blood clotting from the intense magnetic field

Figure E7-1

Figure E7-3

Figure E9-3