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

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 43 dB below
B	At least 63 dB below
C	At least 53 dB below
D	At least 73 dB below

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	IARP agreement
B	All of these choices are correct
C	ITU reciprocal license
D	CEPT agreement

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
C	Any amateur station designated by NASA
D	All of these choices are correct

5. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Relatives of the VE as listed in the FCC rules
B	All of these choices are correct
C	Employees of the VE
D	Friends of the VE

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Amateur Extra Class operators
B	Any licensed amateur operator
C	Only General, Advanced or Amateur Extra Class operators
D	Only Technician, General, Advanced or Amateur Extra Class operators

7. - E2A13

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

Select	Answer
A	Geostationary
B	HEO
C	LEO
D	Geomagnetic

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

Select	Answer
A	The vestigial sideband carries the audio information
B	The vestigial sideband contains chroma information
C	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
D	Vestigial sideband provides high frequency emphasis to sharpen the picture

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	/R# where # is the district of the remote station
B	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
C	The ARRL section of the remote station
D	No additional indicator is required

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To relay messages between satellites
B	To delay download of telemetry between satellites
C	To upload operational software for the transponder
D	To store digital messages in the satellite for later download by other stations

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	The protocol version you are using is not the supported by the digital station
B	Your transmit frequency is incorrect
C	Another station you are unable to hear is using the frequency
D	All of these choices are correct

12. - E3A09

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

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

13. - E3B09

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

Select	Answer
A	Around the equinoxes, especially the fall equinox
B	Around the equinoxes, especially the spring equinox
C	Around the solstices, especially the summer solstice
D	Around the solstices, especially the winter solstice

14. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	Waning sunspot numbers
B	An extreme geomagnetic storm
C	Very low solar activity
D	Moderate solar wind

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	A Q meter
B	A spectrum analyzer
C	An antenna analyzer
D	An ohmmeter

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Temperature coefficient of the logic
B	Time base accuracy
C	Input attenuator accuracy
D	Decade divider accuracy

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	13.845 MHz
B	14.755 MHz
C	14.445 MHz
D	15.210 MHz

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	146.88 MHz and 146.34 MHz
B	146.10 MHz and 147.30 MHz
C	173.35 MHz and 139.40 MHz
D	146.34 MHz and 146.61 MHz

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	Nearby signals may appear to be excessively wide even if they meet emission standards
B	Received audio in the speech range might have an echo effect
C	The audio frequency bandwidth of the received signal might be compressed
D	FM signals can no longer be demodulated

20. - E5A05

What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?

Select	Answer
A	Minimum
B	R/L
C	Maximum
D	L/R

21. - E5B09

What is the relationship between the current through a capacitor and the voltage across a capacitor?

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

22. - E5C09

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

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

23. - E5D01

What is the result of skin effect?

Select	Answer
A	Thermal effects on the surface of the conductor decrease the impedance
B	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface
C	Thermal effects on the surface of the conductor increase the impedance
D	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface

24. - E6A03

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

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

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Tunnel diode
B	Zener diode
C	Varactor diode
D	Silicon-controlled rectifier

26. - E6C07

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

Select	Answer
A	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
B	A resistor in a keying circuit used to reduce key clicks
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. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Select	Answer
A	Powdered-iron cores generally require fewer turns to produce a given inductance
B	Powdered-iron cores generally maintain their characteristics at higher currents
C	Powdered-iron cores generally have greater initial permeability
D	Powdered-iron cores use smaller diameter wire for the same inductance

28. - E6E03

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

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

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of light to electrical energy
B	The conversion of voltage to current when exposed to light
C	The conversion of electrical energy to mechanical energy
D	The tendency of a battery to discharge when used outside

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It maintains a constant output voltage, regardless of variations in the input voltage
B	It switches momentarily to the opposite binary state and then returns to its original state after a set time
C	It produces a continuous square wave oscillating between 1 and 0
D	It stores one bit of data in either a 0 or 1 state

31. - E7B10

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

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

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Cascode
B	Omega
C	Pi-L
D	Pi

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Prevention of battery damage due to overcharge
B	Control of electrolyte levels during battery discharge
C	Matching of day and night charge rates
D	Prevention of battery undercharge

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 de-emphasis network
D	A heterodyne suppressor

35. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	Select the point at which baseband signals are generated
B	Provide access for debugging software
C	Provide incremental signal delays for filter algorithms
D	To reduce excess signal pressure levels

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	24
B	94
C	47
D	0.21

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A diode-switching matrix synthesizer
B	A phase locked loop synthesizer
C	A hybrid synthesizer
D	A direct digital synthesizer

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	All of these choices are correct
B	Very low power consumption decreases frequency drift
C	Very high speed allows digitizing high frequencies
D	Immunity to out of sequence coding reduces spurious responses

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A digital mode for narrow band, slow speed transmissions
B	A frequency modulation technique which uses non-harmonically related frequencies
C	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
D	A bandwidth compression technique using Fourier transforms

40. - E8C10

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

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

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	High-pass filters at the transmitter output
B	Low-pass filters at the transmitter output
C	Reduce keying waveform rise and fall times
D	Increase keying waveform rise and fall times

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	Take-off angle
B	The standing wave ratio
C	Distance from the transmitter
D	Soil conductivity

43. - E9B05

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

Select	Answer
A	Elevation
B	Radiation resistance
C	Azimuth
D	Polarization

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	450 ohms
B	300 ohms
C	72 ohms
D	50 ohms

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 increase the SWR bandwidth
C	To lower the Q
D	To lower the losses

46. - E9E13

What is a use for a Wilkinson divider?

Select	Answer
A	It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedance
B	It is used to feed low-impedance loads from a high-impedance source
C	It is used to feed high-impedance antennas from a low-impedance source
D	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band

47. - E9F12

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

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

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The reactance axis
B	The voltage axis
C	The resistance axis
D	The current axis

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It provides diversity reception that cancels multipath signals
B	It allows DF antennas to receive signals at different vertical angles
C	It modifies the pattern of a DF antenna array to provide a null in one direction
D	It increases the sensitivity of a DF antenna array

50. - E0A06

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

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

Figure E7-1

Figure E7-4

Figure E9-2

Figure E9-3