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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	12 meter band
B	30 meter band
C	17 meter band
D	60 meter band

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Puerto Rico surrounding the Arecibo Radio Telescope
B	An area in New Mexico surrounding the White Sands Test Area
C	An area in Florida surrounding Cape Canaveral
D	An area surrounding the National Radio Astronomy Observatory

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

Select	Answer
A	Only beacon, repeater or space stations
B	Only auxiliary, repeater or space stations
C	Only auxiliary, beacon or space stations
D	Only earth stations, repeater stations or model craft

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
B	An amateur station located more than 50 km above the Earth's surface
C	An amateur station that transmits telemetry consisting of measurements of upper atmosphere
D	An amateur station that transmits communications to initiate, modify or terminate functions of a space station

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	3
B	2
C	4
D	5

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

Select	Answer
A	None, they must obtain a U.S. license
B	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
C	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
D	All privileges of the Extra Class license

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	A log-periodic dipole array
B	A circularly polarized antenna
C	An isotropic antenna
D	A linearly polarized antenna

8. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	A special front end limiter
B	A special notch filter to remove synchronization pulses
C	A special IF converter
D	No other hardware is needed

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

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	It controls the receiver to track Doppler shift
B	It can decode signals many dB below the noise floor using FEC
C	All of these choices are correct
D	It supplies signals to guide the antenna to track the Moon

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	Automatic
B	Remote
C	Local
D	ALE can use any type of control

12. - E3A05

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

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

13. - E3B03

What is the best time of day for transequatorial propagation?

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

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Elliptical
B	Vertical
C	Circular
D	Horizontal

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Automatic amplitude and frequency numerical readout
B	All of these choices are correct
C	Manipulation of time base after trace capture
D	Storage of traces for future reference

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	14.652 Hz
B	1.4652 Hz
C	0.1 MHz
D	1.4652 kHz

17. - E4C05

What does a value of -174 dBm/Hz represent with regard to the noise floor of a receiver?

Select	Answer
A	The minimum detectable signal as a function of receive frequency
B	The theoretical noise at the input of a perfect receiver at room temperature
C	The noise figure of a 1 Hz bandwidth receiver
D	The galactic noise contribution to minimum detectable signal

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To store often-used frequencies
B	To allow selection of the optimum RF amplifier device
C	To provide a range of AGC time constants
D	To increase rejection of unwanted signals

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. - E5A04

What is the magnitude of the impedance of a circuit with a resistor, an inductor and a capacitor all in parallel, at resonance?

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

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Voltage and current are 180 degrees out of phase
B	Voltage and current are in phase
C	Current leads voltage by 90 degrees
D	Voltage leads current by 90 degrees

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By phase angle and amplitude
B	By real and imaginary parts
C	By X and R values
D	By Y and G values

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The diameter of the conductor
B	The resistance divided by the current
C	The amount of current flowing through the conductor
D	The ratio of the current to the resistance

24. - E6A13

What do the initials CMOS stand for?

Select	Answer
A	Common Mode Oscillating System
B	Complementary Mica-Oxide Silicon
C	Common Mode Organic Silicon
D	Complementary Metal-Oxide Semiconductor

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	An integrated circuit logic family using both bipolar and CMOS transistors
B	A logic device with two CMOS circuits per package
C	A logic family based on bismuth CMOS devices
D	A FET logic family based on bimetallic semiconductors

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	79 turns
B	141 turns
C	35 turns
D	13 turns

28. - E6E03

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

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

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A display that uses a glowing liquid to remain brightly lit in dim light
B	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
C	A frequency-determining unit for a transmitter or receiver
D	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency

30. - E7A10

What is a truth table?

Select	Answer
A	A table of logic symbols that indicate the logic states of an op-amp
B	A table of logic symbols that indicate the high logic states of an op-amp
C	A list of inputs and corresponding outputs for a digital device
D	A diagram showing logic states when the digital device output is true

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

Select	Answer
A	Transmission of spurious signals
B	Low efficiency
C	Creation of parasitic oscillations
D	All of these choices are correct

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A Chebyshev filter
B	A passive op-amp filter
C	An active LC filter
D	A Butterworth filter

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 Zener diode
C	An SCR
D	A tunnel diode

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Discriminator
B	Phase comparator
C	Product detector
D	Phase detector

35. - E7F12

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

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

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	As a high-pass filter used to block RFI at the input to receivers
B	As a low-pass filter used between a transmitter and a transmission line
C	For smoothing power supply output
D	As an audio filter in a receiver

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Spurious signals at discrete frequencies
B	Nyquist limit noise
C	Broadband noise
D	Digital conversion noise

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

Select	Answer
A	A sawtooth wave
B	A square wave
C	A sine wave
D	A cosine wave

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	1.67
B	0.167
C	60
D	0.6

40. - E8C06

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

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

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	The generation of RF harmonics
B	Limits data speed
C	The generation of key clicks
D	More difficult to copy

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(total resistance / radiation resistance) x 100 per cent
B	(effective radiated power / transmitter output) x 100 percent
C	(radiation resistance / transmission resistance) x 100 per cent
D	(radiation resistance / total resistance) x 100 per cent

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	The E-field and H-field patterns may reverse
B	Feed point impedance may become negative
C	Element spacing limits could be exceeded
D	The gain may change depending on frequency

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A portable antenna erected using two push support poles
B	A wideband vertical antenna constructed from precisely tapered aluminum tubing
C	An end fed folded dipole antenna
D	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	At a voltage node
B	Near the center of the vertical radiator
C	As low as possible on the vertical radiator
D	As close to the transmitter as possible

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 epsilon match
B	The stub match
C	The gamma match
D	The delta match

47. - E9F03

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

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

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It has a bidirectional pattern
B	It is non-rotatable
C	It is practical for use only on VHF bands
D	It receives equally well in all directions

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

Select	Answer
A	Use an antenna modeling program to calculate field strength at accessible locations
B	Use a hand calculator plus Smith-chart equations to calculate the fields
C	Use a calibrated antenna analyzer
D	All of the choices are correct