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

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	3 miles
B	10 miles
C	30 miles
D	1 mile

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 station through a local auxiliary link
D	Controlling a repeater using a portable handheld transceiver

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
B	One-way transmission of measurements at a distance from the measuring instrument
C	Two-way radiotelephone transmissions in excess of 1000 feet
D	Two-way single channel transmissions of data

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Send the application form to the FCC and inform the FCC of the grade
B	Maintain the application form with the VEC's records
C	Return the application document to the examinee
D	Destroy the application form

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide additional spectrum for personal use
B	To allow regular operation on Land Mobile channels
C	To provide temporary operation while awaiting normal licensing
D	To provide for experimental amateur communications

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The type of signals that can be relayed through the satellite
B	The satellite's uplink and downlink frequency bands
C	The satellite's orientation with respect to the Earth
D	Whether the satellite is in a polar or equatorial orbit

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
B	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
C	They are not permitted above 54 MHz
D	None; they are allowed on all amateur frequencies

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	In the middle of the band, usually 25 kHz above the national calling frequency
B	In the weak signal segment of the band, with most of the activity near the calling frequency
C	At the top of each band, usually in a segment reserved for contests
D	In the middle of each band, usually on the national calling frequency

10. - E2D13

What type of modulation is used for JT65 contacts?

Select	Answer
A	RTTY
B	PSK
C	IEEE 802.11
D	Multi-tone AFSK

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	316 Hz
B	2.16 kHz
C	550 Hz
D	31 Hz

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
B	A wave of alternating current, in the core of an electromagnet
C	A wave consisting of two electric fields at parallel right angles to each other
D	A wave consisting of two magnetic fields at right angles to each other

13. - E3B09

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

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

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	Four times as great
B	10 percent greater
C	Twice as great
D	50 percent greater

15. - E4A05

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

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

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	146.52 Hz
B	146.52 kHz
C	1465.20 Hz
D	10 Hz

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It decreases receiver third-order intermodulation distortion dynamic range
B	It limits the receiver's ability to receive strong signals
C	It reduces receiver sensitivity
D	It can cause strong signals on nearby frequencies to interfere with reception of weak signals

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

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Differential-mode current
B	Return current
C	Reactive current only
D	Common-mode current

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	Matching bandwidth is decreased
B	It has no effect on impedance matching
C	Matching range is increased
D	Matching bandwidth is increased

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	14 degrees with the voltage lagging the current
B	76 degrees with the voltage leading the current
C	76 degrees with the voltage lagging the current
D	14 degrees with the voltage leading the current

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	Resistive component
D	The sum of the reactive and resistive components

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as heat in the circuit
B	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
C	It is dissipated in the formation of inductive and capacitive fields
D	It is dissipated as kinetic energy in the circuit

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. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Reverse voltage larger than the RF signal
B	Capacitance of an RF coupling capacitor
C	A sub-harmonic pump signal
D	Forward DC bias current

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Differential output capability
B	Immune to damage from static discharge
C	Lower power consumption
D	Lower distortion

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Electrolytic capacitors
B	Ferrite beads
C	Steel-core toroids
D	Butterworth filters

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	SOT
B	PLCC
C	Ball grid array
D	DIP

29. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A device which detects rotation of a control by interrupting a light source with a patterned wheel
B	A device which measures the strength of a beam of light using analog to digital conversion
C	A device for generating RTTY signals by means of a rotating light source
D	A digital encryption device often used to encrypt spacecraft control signals

30. - E7A11

What type of logic defines "1" as a high voltage?

Select	Answer
A	Negative logic
B	Positive Logic
C	Assertive Logic
D	Reverse Logic

31. - E7B08

How can an RF power amplifier be neutralized?

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

32. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Select	Answer
A	Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
B	A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
C	An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
D	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	It eliminates the need for a pass transistor
B	It has a ramp voltage as its output
C	The conduction of a control element is varied to maintain a constant output voltage
D	The control element duty cycle is proportional to the line or load conditions

34. - E7E06

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

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

35. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A Hilbert-transform filter
B	A phase-inverting filter
C	An adaptive filter
D	A crystal-lattice filter

36. - E7G08

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

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

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit also known as a monostable multivibrator
B	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
C	An electronic circuit consisting of a precision push-pull amplifier with a differential input
D	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator

38. - E8A07

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

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

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 decreases as the RF carrier frequency increases
D	It does not depend on the RF carrier frequency

40. - E8C06

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

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

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It uses one character as a shift code to send numeric and special characters
B	It contains fewer information bits per character than any other code
C	It is possible to transmit both upper and lower case text
D	It includes built in error correction features

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	Soil conductivity
C	Distance from the transmitter
D	The standing wave ratio

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of segments, each having a distinct value of voltage across it
B	A wire is modeled as a series of segments, each having a uniform value of current
C	A wire is modeled as a single sine-wave current generator
D	A wire is modeled as a series of points, each having a distinct location in space

44. - E9C05

What is an OCFD antenna?

Select	Answer
A	A remotely tunable dipole antenna using orthogonally controlled frequency diversity
B	A dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
C	A multiband dipole antenna using one-way circular polarization for frequency diversity
D	An eight band dipole antenna using octophase filters

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	It becomes flat
B	It is increased
C	It is decreased
D	No change occurs

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The omega match
B	The stub match
C	The gamma match
D	The delta match

47. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
B	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
C	The ratio of the characteristic impedance of the line to the terminating impedance
D	The index of shielding for coaxial cable

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Coaxial-length circles
B	Antenna-length circles
C	Radiation-pattern circles
D	Standing wave ratio circles

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By winding adjacent turns in opposing directions
B	By increasing either the number of wire turns in the loop or the area of the loop structure or both
C	By reducing the permeability of the loop shield
D	By increasing the number of wire turns in the loop and reducing the area of the loop structure

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

Select	Answer
A	By the yellowish appearance of the gas
B	Any ordinary smoke detector can be used
C	By the odor
D	Only with a carbon monoxide detector