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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	1 kHz below the upper band edge
B	3 kHz below the upper band edge
C	300 Hz below the upper band edge
D	The exact upper band edge

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	A proposal must be submitted to the National Park Service
C	A letter of intent must be filed with the National Audubon Society
D	An Environmental Assessment must be submitted to the FCC

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under local control a control operator is not required to be present at a control point
B	Under local control there is no control operator
C	Under automatic control there is no control operator
D	Under automatic control the control operator is not required to be present at the control point

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. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and send the documents to the FCC according to instructions
B	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions
C	They must collect and submit the documents to the coordinating VEC for grading
D	They must collect and send the documents to the NCVEC for grading

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	440 MHz - 450 MHz
B	53 MHz - 54 MHz
C	420 MHz - 430 MHz
D	222 MHz - 223 MHz

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The time it takes for a satellite to complete one revolution around the Earth
B	The point of maximum height of a satellite's orbit
C	The time it takes for a satellite to travel from perigee to apogee
D	The point of minimum height of a satellite's orbit

8. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To identify the SSTV mode being used
B	To lock the color burst oscillator in color SSTV images
C	To provide vertical synchronization
D	To identify the call sign of the station transmitting

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

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Disconnect
B	Connect
C	Unnumbered Information
D	Acknowledgement

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	110 baud
B	48 baud
C	1200 baud
D	300 baud

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the MUF is above 30 MHz
B	When the Moon is at perigee
C	When the Moon is at apogee
D	When the Moon is full

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

Select	Answer
A	Long path and short path waves
B	Refracted rays and reflected waves
C	Independent waves created in the ionosphere that are elliptically polarized
D	Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances

14. - E3C13

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

Select	Answer
A	Elliptical
B	Vertical
C	Horizontal
D	Circular

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	Match the antenna to the load
B	Attenuate the transmitter output going to the spectrum analyzer
C	All of these choices are correct
D	Use high quality double shielded coaxial cables to reduce signal losses

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	The relative time between measurements
B	Frequency order of the measurements
C	Relative quality of the data
D	The port or ports at which measurements are made

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	One-half the maximum sample rate
B	The maximum count value of the analog-to-digital converter
C	The reference voltage of the analog-to-digital converter
D	One-half the maximum sampling buffer size

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	The desired signal can no longer be heard
B	A reduction in apparent signal strength
C	The off-frequency unwanted signal is heard in addition to the desired signal
D	A large increase in background noise

19. - E4E09

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

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

20. - E5A17

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

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

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage leading the current
B	68.2 degrees with the voltage lagging the current
C	14.0 degrees with the voltage lagging the current
D	68.2 degrees with the voltage leading the current

22. - E5C05

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

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

23. - E5D04

Why are short connections necessary at microwave frequencies?

Select	Answer
A	To increase neutralizing resistance
B	Because of ground reflections
C	To reduce noise figure
D	To reduce phase shift along the connection

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Donor impurity
B	Acceptor impurity
C	N-type impurity
D	Insulator impurity

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	1
B	6
C	5
D	7

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	A PGA contains its own internal power supply
B	All of these choices are correct
C	Many similar gates are less expensive than a mixture of gate types
D	Complex logic functions can be created in a single integrated circuit

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Resistance
B	Thermal impedance
C	Reactivity
D	Permeability

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Microstrip construction
B	Point-to-point construction
C	Wave-soldering construction
D	Ground-plane construction

29. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	12 V
B	0.5 V
C	1.5 V
D	0.1 V

30. - E7A06

What is a characteristic of a monostable multivibrator?

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

31. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

Select	Answer
A	Tune both the input and output for maximum power
B	Use a phase inverter in the output filter
C	Install parasitic suppressors and/or neutralize the stage
D	Tune the stage for maximum SWR

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A power supply filter made with interlaced quartz crystals
B	A filter with wide bandwidth and shallow skirts made using quartz crystals
C	An audio filter made with four quartz crystals that resonate at 1kHz intervals
D	A filter with narrow bandwidth and steep skirts made using quartz crystals

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Switching voltage regulator
B	Linear voltage regulator
C	Grounded emitter amplifier
D	Emitter follower

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A heterodyne suppressor
B	A pre-emphasis network
C	A de-emphasis network
D	An audio prescaler

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Reference voltage level and sample width in bits
B	Data storage transfer rate
C	Missing codes and jitter
D	Sample clock phase noise

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

Select	Answer
A	Restrict gain but increase Q
B	Restrict both gain and Q
C	Restrict Q but increase gain
D	Increase both gain and Q

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The amplitude values that represent a sine-wave output
B	The phase relationship between a reference oscillator and the output waveform
C	The phase relationship between a voltage-controlled oscillator and the output waveform
D	The synthesizer frequency limits and frequency values stored in the radio memories

38. - E8A08

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

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

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
B	The ratio of the highest audio modulating frequency to the average audio modulating frequency
C	The ratio of the carrier center frequency to the audio modulating frequency
D	The ratio of the audio modulating frequency to the center carrier frequency

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 26 Hz
B	Approximately 104 Hz
C	Approximately 52 Hz
D	Approximately 13 Hz

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

Select	Answer
A	+15 dB
B	-20 dB
C	-30 dB
D	+10 dB

42. - E9A09

How is antenna efficiency calculated?

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

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	15 dB
B	28 dB
C	24 dB
D	3 dB

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

Select	Answer
A	Cardioid
B	Omni-directional
C	A figure-8 end-fire along the axis of the array
D	A figure-8 broadside to the axis of the array

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

Select	Answer
A	To minimize losses
B	To minimize the Q
C	To maximize losses
D	To swamp out harmonics

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	Pi-L-network
B	A series capacitor
C	Pi-network
D	A shunt inductor

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	3.5 meters
B	0.2 meters
C	20 meters
D	2.3 meters

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and reactance
B	Resistance and voltage
C	Reactance and voltage
D	Voltage and impedance

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	The geometric angles of sky waves from the source are used to determine its position
B	Antenna headings from several different receiving locations are used to locate the signal source
C	A fixed receiving station plots three headings to the signal source
D	A fixed receiving station uses three different antennas to plot the location of the signal source

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Only commercial transmitters
B	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
C	Only the most powerful transmitter
D	Each transmitter operating with a duty-cycle greater than 50 percent

Figure E6-3

Figure E7-3

Figure E9-2