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

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1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

Select	Answer
A	Yes, because the displayed frequency is within the 75 meter phone band segment
B	No, the sideband will extend beyond the edge of the phone band segment
C	Yes, because the DX station initiated the contact
D	No, U.S. stations are not permitted to use phone emissions below 3.610 MHz

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 53 dB below
B	At least 63 dB below
C	At least 43 dB below
D	At least 73 dB below

3. - E1C07

What is meant by local control?

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

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

5. - E1E01

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

Select	Answer
A	4
B	3
C	5
D	2

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
B	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
C	All of these choices are correct
D	The transmission must not be used to obscure the meaning of any communication

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	An isotropic antenna
C	A circularly polarized antenna
D	A linearly polarized antenna

8. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

Select	Answer
A	6 MHz
B	2 MHz
C	3 kHz
D	600 Hz

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
B	The acceptable practice of manually posting the call signs of stations on a spotting network
C	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
D	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station

10. - E2D02

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

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

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Fatal Error Correction
B	Forward Error Correction
C	First Error Correction
D	Final Error Correction

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	The rain must be within radio range of both stations
B	All of these choices are correct
C	Rain droplets must be within the E layer
D	Rain droplets must be electrically charged

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two continents by way of ducts along the magnetic equator
B	Propagation between any two points located on the magnetic equator
C	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
D	Propagation between two stations at the same latitude

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Higher levels of solar UV radiation
B	Decreasing disruption of the geomagnetic field
C	Increasing disruption of the geomagnetic field
D	An increase in the critical frequency

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

Select	Answer
A	Input capacitance
B	Sample resolution
C	Sampling rate
D	Input impedance

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	125 watts
B	25 watts
C	100 watts
D	75 watts

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The maximum detectable spectrum
B	The minimum discernible signal
C	The meter display sensitivity
D	The multiplex distortion stability

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The difference in dB between the noise floor and the third order intercept point
B	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
C	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor
D	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

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

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
B	It is at a maximum
C	It is at a minimum
D	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance

21. - E5B06

What is susceptance?

Select	Answer
A	The magnetic impedance of a circuit
B	The inverse of reactance
C	A measure of the efficiency of a transformer
D	The ratio of magnetic field to electric field

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	Reactive component
B	The difference between the resistive and reactive components
C	The sum of the reactive and resistive components
D	Resistive component

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

24. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

Select	Answer
A	Only N-type semiconductor material can conduct current
B	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
C	Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
D	Only P-type semiconductor material can conduct current

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A negative resistance region
B	A constant voltage drop under conditions of varying current
C	A constant current drop under conditions of varying voltage
D	An internal capacitance that varies with the applied voltage

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To cause the output to change states continually
B	To allow the comparator to be used with AC input signal
C	To increase the sensitivity
D	To prevent input noise from causing unstable output signals

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

Select	Answer
A	Ceramic
B	Brass
C	Ferrite
D	Powdered-iron

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Surface mount
B	Direct soldering
C	Stripped lead
D	Virtual lead mounting

29. - E6F13

What is a liquid crystal display (LCD)?

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

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Monostable multivibrator
B	Astable multivibrator
C	J-K flip-flop
D	T flip-flop

31. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common emitter
B	Common collector
C	Common base
D	Emitter follower

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Higher efficiency
B	Greater transformation range
C	Greater harmonic suppression
D	Lower losses

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	It gives a ramp voltage at its output
B	The controlled device's duty cycle is changed to produce a constant average output voltage
C	It is generally less efficient than a linear regulator
D	The resistance of a control element is varied in direct proportion to the line voltage or load current

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The frequency components present in the modulating signal
B	The unmodulated bandwidth of the transmitted signal
C	The lowest frequency band that the transmitter or receiver covers
D	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency

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

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 high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
C	A digital audio amplifier whose characteristics are determined by components external to the amplifier
D	A RF amplifier used in the UHF and microwave regions

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. - E8A13

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

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

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	60
C	0.6
D	0.167

40. - E8C04

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

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

41. - E8D04

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

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

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

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Radiation resistance
B	Elevation
C	Polarization
D	Azimuth

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

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The front-to-back ratio decreases
B	The SWR is reduced
C	The front-to-back ratio increases
D	The frequency response is widened over the whole frequency band

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The stub matching system
B	The omega matching system
C	The gamma matching system
D	The delta matching system

47. - E9F15

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

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

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 antenna electrical wavelength
C	In fractions of transmission line electrical wavelength
D	In fractions of transmission line electrical frequency

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 practical for use only on VHF bands
C	It receives equally well in all directions
D	It is non-rotatable

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Make sure signals from your station are less than the uncontrolled MPE limits
B	You need only evaluate exposure levels on your own property
C	Advise your neighbors of the results of your tests
D	Make sure signals from your station are less than the controlled MPE limits

Figure E7-1

Figure E9-2