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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the lowest frequency of the channel
B	At the highest frequency of the channel
C	On any frequency where the signal's sidebands are within the channel
D	At the center frequency of the channel

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Puerto Rico surrounding the Arecibo Radio Telescope
B	An area in Florida surrounding Cape Canaveral
C	An area surrounding the National Radio Astronomy Observatory
D	An area in New Mexico surrounding the White Sands Test Area

3. - E1C07

What is meant by local control?

Select	Answer
A	Controlling a repeater using a portable handheld transceiver
B	Controlling a station through a local auxiliary link
C	Direct manipulation of the transmitter by a control operator
D	Automatically manipulating local station controls

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
B	The space station must cease all transmissions after 5 years
C	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
D	All of these choices are correct

5. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Immediately terminate the candidate's examination
B	Immediately terminate everyone's examination and close the session
C	Allow the candidate to complete the examination, but invalidate the results
D	Warn the candidate that continued failure to comply will result in termination of the examination

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must produce full legal output when driven by not more than 5 watts of mean RF input power
B	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
C	It must exhibit a gain of 0 dB or less over its full output range
D	It must be capable of external RF switching between its input and output networks

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 orientation with respect to the Earth
C	Whether the satellite is in a polar or equatorial orbit
D	The satellite's uplink and downlink frequency bands

8. - E2B11

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

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

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Operators are permitted to make contacts even if they do not submit a log
B	Every contest requires a signal report in the exchange
C	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
D	Interference to other amateurs is unavoidable and therefore acceptable

10. - E2D13

What type of modulation is used for JT65 contacts?

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

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

12. - E3A09

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

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

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	The MUF for chordal hop propagation is much lower than for normal skip propagation
B	Signals travel faster along ionospheric chords
C	The signal experiences less loss along the path compared to normal skip propagation
D	Atmospheric noise is lower in the direction of chordal hop propagation

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to aurora refraction
B	D-region skip
C	Downward bending due to density variations in the atmosphere
D	E-region skip

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A spectrum analyzer
B	A wattmeter
C	A logic analyzer
D	A time-domain reflectometer

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	Low reluctance input
B	High impedance input
C	High reluctance input
D	Low impedance input

17. - E4C15

What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Select	Answer
A	Detector noise
B	Atmospheric noise
C	Induction motor noise
D	Receiver front-end noise

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To provide a range of AGC time constants
B	To store often-used frequencies
C	To allow selection of the optimum RF amplifier device
D	To increase rejection of unwanted signals

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	The broadcast station is transmitting an over-modulated signal
B	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
C	Your station receiver IF amplifier stage is defective
D	You are receiving sky wave signals from a distant station

20. - E5A13

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

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

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

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The tangent and cotangent values
B	The sine and cosine values
C	The magnitude and phase of the point
D	The coordinate values along the horizontal and vertical axes

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By dividing the reactive power by the power factor
B	By dividing the apparent power by the power factor
C	By multiplying the reactive power times the power factor
D	By multiplying the apparent power times the power factor

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Corner frequency
B	Beta cutoff frequency
C	Alpha cutoff frequency
D	Alpha rejection frequency

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Reverse bias controls its forward voltage drop
B	A large region of intrinsic material
C	Extremely high reverse breakdown voltage
D	Ability to dissipate large amounts of power

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	All of these choices are correct
B	Its simplicity results in much less expensive devices than standard CMOS
C	It is totally immune to electrostatic damage
D	It has the high input impedance of CMOS and the low output impedance of bipolar transistors

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	Trimmer capacitor
B	Snubber capacitor
C	Feedback capacitor
D	Clipper capacitor

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Low leakage doubly insulated package
B	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
C	Two chips in each package (Dual In Package)
D	Package mounts in a direct inverted position

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators eliminate the effects of reflected light in the control circuit
B	Optoisolators provide a low impedance link between a control circuit and a power circuit
C	Optoisolators provide impedance matching between the control circuit and power circuit
D	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched

30. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic "0" at its output only when all inputs are logic "0"
B	It produces logic "0" at its output if some but not all inputs are logic "1"
C	It produces logic "1" at its output only when all inputs are logic "1"
D	It produces logic "0" at its output only when all inputs are logic "1"

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	Linear amplifiers have high gain resulting in higher harmonic content
B	Switching amplifiers operate at higher voltages
C	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
D	Switching amplifiers use push-pull circuits

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

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

34. - E7E10

How does a diode detector function?

Select	Answer
A	By mixing signals with noise in the transition region of the diode
B	By breakdown of the Zener voltage
C	By rectification and filtering of RF signals
D	By sensing the change of reactance in the diode with respect to frequency

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 phase-inverting filter
B	A Hilbert-transform 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 does not vary with frequency
C	It decreases logarithmically with increasing frequency
D	It increases linearly with increasing frequency

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Toroidal inductors
B	Wirewound resistors
C	Non-inductive resistors
D	NP0 capacitors

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A square wave
B	A sine wave
C	A sawtooth wave
D	A cosine wave

39. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	3000
B	0.3
C	3
D	1000

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Symbol rate is only used for packet-based modes
B	Baud is twice the symbol rate
C	They are the same
D	Baud is only used for RTTY

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
B	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
C	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
D	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Radiation resistance plus space impedance
B	Transmission-line resistance plus radiation resistance
C	Radiation resistance plus transmission resistance
D	Radiation resistance plus ohmic resistance

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	Feed point impedance may become negative
B	The gain may change depending on frequency
C	Element spacing limits could be exceeded
D	The E-field and H-field patterns may reverse

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

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

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The frequency response is widened over the whole frequency band
B	The front-to-back ratio increases
C	The SWR is reduced
D	The front-to-back ratio decreases

46. - E9E06

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

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

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	71 meters
B	15 meters
C	10 meters
D	20 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 antenna electrical wavelength
C	In fractions of transmission line electrical frequency
D	In fractions of transmission line electrical wavelength

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	Its overall length must not exceed 1/4 wavelength
B	It should be one or more wavelengths long
C	It must be mounted more than 1 wavelength above ground
D	It should be configured as a four-sided loop

50. - E0A07

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

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