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

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	All amateur service frequencies authorized to the control operator
B	Specific local government channels
C	Specific segments in the amateur service MF, HF, VHF and UHF bands
D	Military Auxiliary Radio System (MARS) channels

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	Never
B	When approved by the National Telecommunication and Information Administration
C	When agreed upon by the sending or receiving station
D	Only when transmitting RTTY or data emissions

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
B	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
C	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
D	All HF bands

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

Select	Answer
A	Record the exam session on video tape for later review by the VE team
B	Use a real-time video link and the Internet to connect the exam session to the observing VEs
C	The exam proctor observes the applicants and reports any violations
D	Have each applicant sign an affidavit stating that all session rules were followed

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 50 MHz
B	Only on amateur frequencies above 222 MHz
C	Only on amateur frequencies above 420 MHz
D	Only on amateur frequencies above 144 MHz

7. - E2A03

What is the orbital period of an Earth satellite?

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

8. - E2B14

What aspect of an amateur slow-scan television signal encodes the brightness of the picture?

Select	Answer
A	Sync amplitude
B	Tone amplitude
C	Sync frequency
D	Tone frequency

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 440 MHz transceiver with a 9600 baud modem
B	A standard wireless router running custom software
C	A 2 meter VHF transceiver with a 1200 baud modem
D	An optical cable connection between the USB ports of 2 separate computers

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
C	All of these choices are correct
D	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event

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. - E3A03

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

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

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

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

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The solar emission at 304 GHz, correlated to X-Ray flare levels
B	The ratio of X-Ray flux to radio flux, correlated to sunspot number
C	UV emissions at 304 angstroms, correlated to solar flux index
D	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Bit error rate tester
B	Network analyzer
C	Modulation monitor
D	Logic analyzer

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S11
B	S12
C	S21
D	S22

17. - E4C12

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?

Select	Answer
A	Output-offset overshoot
B	Undesired signals may be heard
C	Thermal-noise distortion
D	Filter ringing

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
B	Oscillator instability and severe audio distortion of all but the strongest received signals
C	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
D	Cross-modulation of the desired signal and desensitization from strong adjacent signals

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

Select	Answer
A	Ringing in the DSP filter will completely remove the spaces between the CW characters
B	Received CW signals will appear to be modulated at the DSP clock frequency
C	Any nearby signal passing through the DSP system will overwhelm the desired signal
D	A DSP filter can remove the desired signal at the same time as it removes interfering signals

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Phase shift can become uncontrolled
B	Internal voltages and circulating currents increase
C	Fewer components are needed for the same performance
D	Parasitic effects are minimized

21. - E5B05

What happens to the magnitude of a reactance when it is converted to a susceptance?

Select	Answer
A	It is shifted by 90 degrees
B	The magnitude of the susceptance is the reciprocal of the magnitude of the reactance
C	The sign is reversed
D	It is unchanged

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 3
B	Point 1
C	Point 8
D	Point 7

23. - E5D13

How much power is consumed in a circuit consisting of a 100 ohm resistor in series with a 100 ohm inductive reactance drawing 1 ampere?

Select	Answer
A	141.4 Watts
B	100 Watts
C	70.7 Watts
D	200 Watts

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	An FET that has no current flow between source and drain when no gate voltage is applied
B	An FET that exhibits a current flow between source and drain when no gate voltage is applied
C	Any FET for which holes are the majority carriers
D	Any FET without a channel

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Controlled reverse avalanche voltage
B	Enhanced carrier retention time
C	Less forward voltage drop
D	Much higher reverse voltage breakdown

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	More efficient arithmetic operations
B	High speed operation
C	Low power consumption
D	Ability to connect many device outputs to a common bus

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

Select	Answer
A	Feedback capacitor
B	Trimmer capacitor
C	Clipper capacitor
D	Snubber capacitor

28. - E6E03

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

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

29. - E6F13

What is a liquid crystal display (LCD)?

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

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic "1" at its output only if all inputs are logic "1"
B	It produces logic "1" at its output if any single input is logic "1"
C	It produces logic "0" at its output only if all inputs are logic "0"
D	It produces logic "0" at its output if any single input is logic "1"

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

Select	Answer
A	All of these choices are correct
B	Creation of parasitic oscillations
C	Transmission of spurious signals
D	Low efficiency

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

Select	Answer
A	A Pi-network with an additional series inductor on the output
B	A matching network in which all components are isolated from ground
C	A network with only three discrete parts
D	A Phase Inverter Load network

33. - E7D08

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

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

34. - E7E06

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

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

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Multiply each sample value by a factor of 3/4
B	Interpolate by a factor of three, then decimate by a factor of four
C	Change the gain by a factor of 3/4
D	Add 3 to each input value and subtract 4 from each output value

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H10

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

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

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	Human speech
B	Data
C	All of these choices are correct
D	Video signals

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more signals are quadrature modulated to increase bandwidth efficiency
B	Two or more signals are arranged to share discrete time slots of a data transmission
C	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
D	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier

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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Excessive transmit audio levels
B	Excessive numbers of retries
C	Bit errors in the modem
D	Ground loops

42. - E9A16

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	2000 watts
B	317 watts
C	300 watts
D	126 watts

43. - E9B06

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

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

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	Omni-directional
B	A figure-8 broadside to the axis of the array
C	Cardioid
D	A figure-8 end-fire along 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 maximize losses
C	To swamp out harmonics
D	To minimize the Q

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It ensures that each driven element operates in concert with the others to create the desired antenna pattern
B	It allows single-band antennas to operate on other bands
C	It makes sure the antenna has a low-angle radiation pattern
D	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	Foam dielectric has lower safe operating voltage limits
B	Foam dielectric has lower loss per unit of length
C	Foam dielectric has higher velocity factor
D	All of these choices are correct

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 resistance axis
C	The voltage axis
D	The current axis

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It is practical for use only on VHF bands
B	It is non-rotatable
C	It has a bidirectional pattern
D	It receives equally well in all directions

50. - E0A02

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

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

Figure E5-2

Figure E7-3

Figure E9-2

Figure E9-3