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

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1. - E1A02

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

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

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	An amateur station transmission made at random without the proper call sign identification
C	A signal transmitted to prevent its detection by any station other than the intended recipient
D	Any transmitted signal that unintentionally interferes with another licensed radio station

3. - E1C07

What is meant by local control?

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

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
B	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
C	All HF bands
D	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	A person who has volunteered to administer amateur operator license examinations
B	The person who has entered into an agreement with the FCC to be the VE session manager
C	A person who has volunteered to prepare amateur operator license examinations
D	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide temporary operation while awaiting normal licensing
B	To allow regular operation on Land Mobile channels
C	To provide for experimental amateur communications
D	To provide additional spectrum for personal use

7. - E2A13

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

Select	Answer
A	LEO
B	Geomagnetic
C	HEO
D	Geostationary

8. - E2B14

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

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

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 between a U.S. station and a non-U.S. station
C	Contacts using tactical call signs
D	Special event contacts between stations in the U.S.

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Unnumbered Information
B	Connect
C	Acknowledgement
D	Disconnect

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 uses a DC-coupled data connection
C	Direct FSK applies the data signal to the transmitter VFO
D	Audio FSK has a superior frequency response

12. - E3A11

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

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

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

Select	Answer
A	1000 miles
B	7500 miles
C	2500 miles
D	5000 miles

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to aurora refraction
B	D-region skip
C	E-region skip
D	Downward bending due to density variations in the atmosphere

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A logic analyzer
B	A wattmeter
C	A spectrum analyzer
D	A time-domain reflectometer

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	25 watts
B	125 watts
C	75 watts
D	100 watts

17. - E4C12

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?

Select	Answer
A	Output-offset overshoot
B	Thermal-noise distortion
C	Undesired signals may be heard
D	Filter ringing

18. - E4D11

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

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

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By turning off the AC power line main circuit breaker and listening on a battery operated radio
B	By checking the power line voltage with a time domain reflectometer
C	By observing the AC power line waveform with an oscilloscope
D	By observing the AC power line voltage with a spectrum analyzer

20. - E5A17

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

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

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	68.2 degrees with the voltage leading the current
B	14.0 degrees with the voltage lagging the current
C	68.2 degrees with the voltage lagging the current
D	14.0 degrees with the voltage leading the current

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The magnitude and phase of the point
B	The sine and cosine values
C	The coordinate values along the horizontal and vertical axes
D	The tangent and cotangent values

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In the same direction as the current
B	In all directions; omni-directional
C	In a direction determined by the left-hand rule
D	In a direction opposite to the current

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	N-type impurity
B	Donor impurity
C	Acceptor impurity
D	Insulator impurity

25. - E6B08

Which of the following describes a type of semiconductor diode?

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

26. - E6C14

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

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

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

Select	Answer
A	141 turns
B	35 turns
C	13 turns
D	79 turns

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

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It decreases
B	It becomes unstable
C	It stays the same
D	It increases

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	An "OR" gate
B	An "AND" gate
C	A flip-flop
D	A clock

31. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

Select	Answer
A	Fixed bias
B	Self bias
C	Feedback
D	Load resistors

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	Network resistances are substituted for load resistances and reactances are matched to the resistances
B	It introduces negative resistance to cancel the resistive part of impedance
C	It cancels the reactive part of the impedance and changes the resistive part to a desired value
D	It introduces transconductance to cancel the reactive part of impedance

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage divided by output current
B	Output voltage multiplied by output current
C	Voltage difference from input to output multiplied by output current
D	Input voltage multiplied by input current

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of an amplifier tank circuit to produce PM signals
B	By varying the tuning of an amplifier tank circuit to produce AM signals
C	By varying the tuning of a microphone preamplifier to produce PM signals
D	By varying the tuning of a microphone preamplifier to produce AM signals

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	4 bits
B	6 bits
C	8 bits
D	10 bits

36. - E7G12

What is an integrated circuit operational amplifier?

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

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

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

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Improve accuracy by removing out of sequence codes from the input
B	All of these choices are correct
C	Remove harmonics from the output caused by the discrete analog levels generated
D	Lower the input bandwidth to increase the effective resolution

39. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	60
B	0.167
C	1.67
D	0.6

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It increases security
B	It facilitates error detection
C	It has more resolution than simple binary
D	It has more possible states than simple binary

41. - E8D10

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

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

42. - E9A07

What is meant by antenna gain?

Select	Answer
A	The ratio of the amount of power radiated by an antenna compared to the transmitter output power
B	The ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
C	The final amplifier gain minus the transmission line losses
D	The ratio of the signal in the forward direction to that in the opposite direction

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	1
B	4
C	3
D	7

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. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To cancel capacitive reactance
B	To lower the losses
C	To increase the SWR bandwidth
D	To lower the Q

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 stub match
C	The gamma match
D	The epsilon match

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

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

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	A very sharp peak
B	Broad band response
C	High-radiation angle
D	A very sharp single null

50. - E0A08

What does SAR measure?

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

Figure E7-1

Figure E9-2