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

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	50 watts PEP effective radiated power relative to a dipole
B	100 watts PEP effective radiated power relative to an isotropic radiator
C	50 watts PEP effective radiated power relative to an isotropic radiator
D	100 watts PEP effective radiated power relative to the gain of a half-wave dipole

2. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must cease operation on all frequencies above 30 MHz
B	The amateur station must cease operation
C	The amateur station must cease operation on all frequencies below 30 MHz
D	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	The U.S. embassy must approve of your operation
B	You must append "/CEPT" to your call sign
C	You must identify in the official language of the country in which you are operating
D	You must bring a copy of FCC Public Notice DA 11-221

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	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
B	All of these choices are correct
C	Any amateur station so designated by the ITU
D	Any amateur station designated by NASA

5. - E1E08

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

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

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 provide additional spectrum for personal use
C	To allow regular operation on Land Mobile channels
D	To provide for experimental amateur communications

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By adding the mean anomaly to the orbital inclination
B	By calculations using the Keplerian elements for the specified satellite
C	By means of the Doppler data for the specified satellite
D	By subtracting the mean anomaly from the orbital inclination

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Chroma
B	Luminance
C	Hue
D	Spectral Intensity

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To separate the calling stations from the DX station
B	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
C	All of these choices are correct
D	To improve operating efficiency by reducing interference

10. - E2D14

What is one advantage of using JT65 coding?

Select	Answer
A	The ability to decode signals which have a very low signal to noise ratio
B	Uses only a 65 Hz bandwidth
C	Easily copied by ear if necessary
D	Permits fast-scan TV transmissions over narrow bandwidth

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK applies the data signal to the transmitter VFO
B	Audio FSK can be performed anywhere in the transmit chain
C	Direct FSK uses a DC-coupled data connection
D	Audio FSK has a superior frequency response

12. - E3A05

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

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

13. - E3B01

What is transequatorial propagation?

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

14. - E3C13

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

Select	Answer
A	Elliptical
B	Horizontal
C	Circular
D	Vertical

15. - E4A14

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

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

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It can display results directly in Smith chart format
B	It is very precise in obtaining a signal null
C	It provides an excellent match under all conditions
D	It is relatively immune to drift in the signal generator source

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio of thermal noise to atmospheric noise
B	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise
C	The ratio of atmospheric noise to phase noise
D	The ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network

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 two signals which produce third order intermodulation products greater than the noise floor
C	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
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. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By installing a noise suppression resistor and a blocking capacitor in both leads
B	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
C	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
D	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

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

21. - E5B12

What is admittance?

Select	Answer
A	The term for the gain of a field effect transistor
B	The turns ratio of a transformer
C	The inverse of impedance
D	The unit used for Q factor

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Phasor diagram
B	Far field diagram
C	Near field diagram
D	Venn diagram

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

24. - E6A17

What are the names of the three terminals of a field-effect transistor?

Select	Answer
A	Gate 1, gate 2, drain
B	Gate, drain, source
C	Emitter, base, collector
D	Emitter, base 1, base 2

25. - E6B06

Which of the following is a common use of a hot-carrier diode?

Select	Answer
A	As a variable capacitance in an automatic frequency control circuit
B	As balanced mixers in FM generation
C	As a constant voltage reference in a power supply
D	As a VHF/UHF mixer or detector

26. - E6C01

What is the function of hysteresis in a comparator?

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

27. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	Inter-turn capacitance
B	Inductive kickback
C	Non-linear core hysteresis
D	The skin effect

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Nearly infinite gain, very high input impedance, and very low output impedance
B	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
C	The ability to retrieve information from a single signal even in the presence of other strong signals
D	Plate current that is controlled by a control grid

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	An LED and a phototransistor
B	A lens and a photomultiplier
C	An amplitude modulated helium-neon laser
D	A frequency modulated helium-neon laser

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It produces one output pulse for every ten input pulses
B	It produces ten output pulses for every input pulse
C	It decodes a decimal number for display on a seven segment LED display
D	It adds two decimal numbers together

31. - E7B08

How can an RF power amplifier be neutralized?

Select	Answer
A	By feeding an in-phase component of the output back to the input
B	By feeding a 180-degree out-of-phase portion of the output back to the input
C	By increasing the driving power
D	By reducing the driving power

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

Select	Answer
A	Meteor scatter
B	Digital
C	Video
D	Single-Sideband voice

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

Select	Answer
A	A shunt current source
B	A shunt regulator
C	A series regulator
D	A constant current source

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	For higher efficiency
B	To remove third-order distortion products
C	To reduce impulse noise reception
D	For compatibility with transmitters using phase modulation

35. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Reducing the effective sample rate by removing samples
B	Converting data to binary code decimal form
C	Removing unnecessary significant digits
D	Attenuating the signal

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	Undesired oscillations added to the desired signal
B	Partial cancellation of the signal over a range of frequencies
C	A reduction in high frequency response
D	An echo caused by a long time delay

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Negative feedback and balanced feedback
B	Colpitts and Hartley
C	Pierce and Zener
D	Armstrong and deForest

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 high speed allows digitizing high frequencies
C	Very low power consumption decreases frequency drift
D	Immunity to out of sequence coding reduces spurious responses

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It varies with the square root of the RF carrier frequency
B	It increases as the RF carrier frequency increases
C	It does not depend on the RF carrier frequency
D	It decreases as the RF carrier frequency increases

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Extended Binary Coded Decimal Interchange Code
B	Gray code
C	Binary Coded Decimal Code
D	Excess 3 code

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to change frequencies
B	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	The receiver is always equipped with a digital blanker

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It is essentially unaffected
B	It decreases
C	It increases geometrically
D	It increases arithmetically

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	7.5 degrees
B	25 degrees
C	45 degrees
D	75 degrees

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The high-angle radiation increases
B	Both the high-angle and low-angle radiation decrease
C	The low-angle radiation increases
D	The low-angle radiation decreases

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
B	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
C	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
D	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element reactance must be inductive
B	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
C	The driven element resonance must be lower than the operating frequency
D	The driven element reactance must be capacitive

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	6.9 meters
B	10 meters
C	50 meters
D	24 meters

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

49. - E9H08

What is the function of a sense antenna?

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

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Reduce received noise
B	Lightning protection
C	Reduce RFI to telephones and home entertainment systems
D	Reduce RF current flow between pieces of equipment

Figure E9-2