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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operator of the packet bulletin board station
B	The control operators of all the stations in the system not authenticating the source from which they accept communications
C	The control operator of the originating station
D	The control operators of all the stations in the system

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	No special rules apply if your antenna structure will be less than 300 feet in height
B	You must file an Environmental Impact Statement with the EPA before construction begins
C	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
D	You must obtain a construction permit from the airport zoning authority

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	The use of a control link between a control point and a locally controlled station
B	A station operating with its output power controlled automatically
C	Remotely controlling a station's antenna pattern through a directional control link
D	The use of devices and procedures for control so that the control operator does not have to be present at a control point

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of General, Advanced or Amateur Extra Class operators
B	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
C	Any amateur station, subject to the privileges of the class of operator license held by the control operator
D	Only those of Amateur Extra Class operators

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 80%
B	Minimum passing score of 74%
C	Minimum passing score of 70%
D	Minimum passing score of 77%

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. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

Select	Answer
A	All of these choices are correct
B	FM and CW
C	PSK and Packet
D	SSB and SSTV

8. - E2B14

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

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

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 2 meter VHF transceiver with a 1200 baud modem
B	A standard wireless router running custom software
C	A 440 MHz transceiver with a 9600 baud modem
D	An optical cable connection between the USB ports of 2 separate computers

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	High speed CW identification to avoid fading
B	Storing and forwarding digital messages
C	Judging optimum transmission times by monitoring beacons reflected from the Moon
D	Time synchronous transmissions alternately from each station

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	Selective fading has occurred
B	The receiver has drifted 5 kHz from the desired receive frequency
C	One of the signal filters is saturated
D	The mark and space signal have been inverted

12. - E3A09

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

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

13. - E3B11

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

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

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately twice the distance
B	By approximately 15 percent of the distance
C	By approximately 50 percent of the distance
D	By approximately four times the distance

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
B	It prevents oscillation in a low-frequency counter circuit
C	It divides a higher frequency signal so a low-frequency counter can display the input frequency
D	It amplifies low level signals for more accurate counting

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	10 Hz
B	146.52 kHz
C	1465.20 Hz
D	146.52 Hz

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Cross-modulation interference
B	Capture effect
C	Frequency discrimination
D	Desensitization

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 intermodulation produces three products for every input signal within the band of interest
C	Third-order products are an indication of poor image rejection
D	The third-order intercept is much higher than other orders

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 observing the AC power line waveform with an oscilloscope
C	By observing the AC power line voltage with a spectrum analyzer
D	By checking the power line voltage with a time domain reflectometer

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	157.8 Hz
B	315.6 Hz
C	47.3 kHz
D	23.67 kHz

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

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	-jX
B	+jX
C	X
D	Omega

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 a direction opposite to the current
C	In all directions; omni-directional
D	In a direction determined by the left-hand rule

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of base current with respect to collector current
B	The change of collector current with respect to emitter current
C	The change of collector current with respect to gate current
D	The change of collector current with respect to base current

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor in a keying circuit used to reduce key clicks
B	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
C	A resistor connected to an op-amp output that only functions when the logic output is false
D	A resistor that insures that an oscillator frequency does not drive lower over time

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	13 turns
B	79 turns
C	35 turns
D	141 turns

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It samples an analog signal and passes it in stages from the input to the output
B	It is used in a battery charger circuit
C	It is a CMOS analog-to-digital converter
D	Its phase shift changes rapidly with frequency

29. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	0.1 V
B	0.5 V
C	1.5 V
D	12 V

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	A flip-flop
B	An OR gate
C	A multiplexer
D	An XOR gate

31. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

Select	Answer
A	Tune both the input and output for maximum power
B	Tune the stage for maximum SWR
C	Install parasitic suppressors and/or neutralize the stage
D	Use a phase inverter in the output filter

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A power supply filter made with interlaced quartz crystals
B	A filter with narrow bandwidth and steep skirts made using quartz crystals
C	A filter with wide bandwidth and shallow skirts made using quartz crystals
D	An audio filter made with four quartz crystals that resonate at 1kHz intervals

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 eliminates the need for a pass transistor
C	It has a ramp voltage as its output
D	The control element duty cycle is proportional to the line or load conditions

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A pre-emphasis network
B	An audio prescaler
C	A heterodyne suppressor
D	A de-emphasis network

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

Select	Answer
A	Signal conditioning
B	Quadrature mixing
C	Decimation
D	Fast Fourier Transform

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It does not vary with frequency
B	It decreases logarithmically with increasing frequency
C	It increases linearly with increasing frequency
D	It decreases linearly with increasing frequency

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 voltage
D	Bias the crystal at a specified current

38. - E8A07

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

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

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the audio modulating frequency to the center carrier frequency
B	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
C	The ratio of the carrier center frequency to the audio modulating frequency
D	The ratio of the highest audio modulating frequency to the average audio modulating frequency

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is only used for RTTY
B	They are the same
C	Baud is twice the symbol rate
D	Symbol rate is only used for packet-based modes

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

Select	Answer
A	Baud rate
B	Signal to noise ratio
C	Repeat Request Rate (RRR)
D	Intermodulation Distortion (IMD)

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

Select	Answer
A	78.7 watts
B	420 watts
C	1977 watts
D	286 watts

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	24 dB
B	3 dB
C	15 dB
D	28 dB

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

Select	Answer
A	A figure-8 end-fire along the axis of the array
B	A figure-8 broadside to the axis of the array
C	Omni-directional
D	Cardioid

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	A single 12 gauge or 10 gauge stainless steel wire
B	A wide flat copper strap
C	A resistive wire, such as spark plug wire
D	A cable with six or seven 18 gauge conductors in parallel

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Connect a parallel-resonant LC network across the antenna feed terminals
B	Use a 50 ohm 1:1 balun between the antenna and feed line
C	Use the universal stub matching technique
D	Connect a series-resonant LC network across the antenna feed terminals

47. - E9F02

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

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

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radiation resistance
B	Radio propagation
C	Impedance along transmission lines
D	Antenna radiation pattern

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	Low loss coax transmission line is essential for good performance
B	Atmospheric noise is so high that gain over a dipole is not important
C	All of these choices are correct
D	They must be erected at least 1/2 wavelength above the ground to attain good directivity

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	Ground reflections and scattering make the field impedance vary with location
B	The body reacts to electromagnetic radiation from both the E and H fields
C	E field and H field radiation intensity peaks can occur at different locations
D	All of these choices are correct

Figure E9-2