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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

SelectAnswer
ADiscontinue forwarding the communication as soon as you become aware of it
BNotify the nearest FCC Field Engineer's office
CDiscontinue forwarding all messages
DNotify the originating station that the communication does not comply with FCC rules

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

SelectAnswer
A0.5
B2.0
C1.0
D3.0

3. - E1C13

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

SelectAnswer
AYou must append "/CEPT" to your call sign
BYou must identify in the official language of the country in which you are operating
CYou must bring a copy of FCC Public Notice DA 11-221
DThe U.S. embassy must approve of your operation

4. - E1D06

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

SelectAnswer
AAll of these choices are correct
BThe space station must be capable of changing its orbit whenever such a change is ordered by NASA
CThe space station must be capable of terminating transmissions by telecommand when directed by the FCC
DThe space station must cease all transmissions after 5 years

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

SelectAnswer
AThe amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
BThe procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
CEach General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
DThe prospective VE obtains accreditation from the FCC

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

SelectAnswer
AA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
BAll of these choices are correct
CThe transmission must not be used to obscure the meaning of any communication
DThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions

7. - E2A12

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

SelectAnswer
ABy adding the mean anomaly to the orbital inclination
BBy calculations using the Keplerian elements for the specified satellite
CBy means of the Doppler data for the specified satellite
DBy subtracting the mean anomaly from the orbital inclination

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

SelectAnswer
AElapsed time
BA two-tone signal
CSpecific tone amplitudes
DSpecific tone frequencies

9. - E2C06

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

SelectAnswer
AIn the weak signal segment of the band, with most of the activity near the calling frequency
BAt the top of each band, usually in a segment reserved for contests
CIn the middle of the band, usually 25 kHz above the national calling frequency
DIn the middle of each band, usually on the national calling frequency

10. - E2D14

What is one advantage of using JT65 coding?

SelectAnswer
APermits fast-scan TV transmissions over narrow bandwidth
BUses only a 65 Hz bandwidth
CThe ability to decode signals which have a very low signal to noise ratio
DEasily copied by ear if necessary

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?

SelectAnswer
AYour transmit frequency is incorrect
BAnother station you are unable to hear is using the frequency
CThe protocol version you are using is not the supported by the digital station
DAll of these choices are correct

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

SelectAnswer
AThe F1 layer
BThe D layer
CThe E layer
DThe F2 layer

13. - E3B05

Which amateur bands typically support long-path propagation?

SelectAnswer
A6 meters to 2 meters
B30 meters to 10 meters
C160 meters to 40 meters
D160 meters to 10 meters

14. - E3C08

What does the space weather term G5 mean?

SelectAnswer
AWaning sunspot numbers
BVery low solar activity
CAn extreme geomagnetic storm
DModerate solar wind

15. - E4A12

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

SelectAnswer
AAttenuate the transmitter output going to the spectrum analyzer
BAll of these choices are correct
CMatch the antenna to the load
DUse high quality double shielded coaxial cables to reduce signal losses

16. - E4B07

What do the subscripts of S parameters represent?

SelectAnswer
AThe relative time between measurements
BFrequency order of the measurements
CRelative quality of the data
DThe port or ports at which measurements are made

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

SelectAnswer
A-148 dBm
B-155 dBm
C-164 dBm
D-174 dBm

18. - E4D07

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

SelectAnswer
AA reduction in apparent signal strength
BThe desired signal can no longer be heard
CThe off-frequency unwanted signal is heard in addition to the desired signal
DA large increase in background noise

19. - E4E12

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

SelectAnswer
AReceived CW signals will appear to be modulated at the DSP clock frequency
BA DSP filter can remove the desired signal at the same time as it removes interfering signals
CAny nearby signal passing through the DSP system will overwhelm the desired signal
DRinging in the DSP filter will completely remove the spaces between the CW characters

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

SelectAnswer
AResistance divided by the reactance of either the inductance or capacitance
BReactance of either the inductance or capacitance divided by the resistance
CReactance of the inductance multiplied by the reactance of the capacitance
DReactance of either the inductance or capacitance multiplied by the resistance

21. - E5B13

What letter is commonly used to represent susceptance?

SelectAnswer
AG
BY
CB
DX

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

SelectAnswer
AA negative real part
BA negative phase angle
CA positive real part
DA positive phase angle

23. - E5D07

What determines the strength of the magnetic field around a conductor?

SelectAnswer
AThe resistance divided by the current
BThe diameter of the conductor
CThe ratio of the current to the resistance
DThe amount of current flowing through the conductor

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?

SelectAnswer
ABeta cutoff frequency
BCorner frequency
CAlpha cutoff frequency
DAlpha rejection frequency

25. - E6B05

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

SelectAnswer
AExtremely high reverse breakdown voltage
BAbility to dissipate large amounts of power
CReverse bias controls its forward voltage drop
DA large region of intrinsic material

26. - E6C08

In Figure E6-5, what is the schematic symbol for a NAND gate?

SelectAnswer
A1
B3
C4
D2

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

SelectAnswer
AFrom about 100 kHz to at least 1000 GHz
BFrom a few kHz to no more than 30 MHz
CFrom approximately 10 Hz to no more than 3000 kHz
DFrom less than 20 Hz to approximately 300 MHz

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

SelectAnswer
A450 ohms
B10 ohms
C50 ohms
D300 ohms

29. - E6F07

What is a solid state relay?

SelectAnswer
AA passive delay line
BA relay using transistors to drive the relay coil
CA mechanical relay that latches in the on or off state each time it is pulsed
DA device that uses semiconductors to implement the functions of an electromechanical relay

30. - E7A12

What type of logic defines "0" as a high voltage?

SelectAnswer
AReverse Logic
BAssertive Logic
CPositive Logic
DNegative logic

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

SelectAnswer
AMore than 180 degrees but less than 360 degrees
BExactly 180 degrees
CLess than 180 degrees
DThe entire cycle

32. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with minimal stop band ripple
BExtremely sharp cutoff with one or more notches in the stop band
CGradual passband rolloff with extreme stop band ripple
DExtremely flat response over its pass band with gradually rounded stop band corners

33. - E7D05

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

SelectAnswer
AA shunt regulator
BA constant current source
CA series regulator
DA shunt current source

34. - E7E06

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

SelectAnswer
ATo reduce impulse noise reception
BFor higher efficiency
CFor compatibility with transmitters using phase modulation
DTo remove third-order distortion products

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
ASoftware is converted from source code to object code during operation of the receiver
BIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
CA switching mixer is used to generate I and Q signals directly from the RF input
DIncoming RF is converted to a control voltage for a voltage controlled oscillator

36. - E7G12

What is an integrated circuit operational amplifier?

SelectAnswer
AA digital audio amplifier whose characteristics are determined by components external to the amplifier
BA RF amplifier used in the UHF and microwave regions
CA high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
DAn amplifier used to increase the average output of frequency modulated amateur signals to the legal limit

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a neutralizing capacitor
CThrough link coupling
DThrough a capacitive divider

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

SelectAnswer
A1 to 1
B25 to 1
C2.5 to 1
D100 to 1

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?

SelectAnswer
A1000
B0.3
C3
D3000

40. - E8C06

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

SelectAnswer
A0.1 Hz
B1.0 kHz
C0.5 kHz
D0.3 kHz

41. - E8D11

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

SelectAnswer
AIt is possible to transmit both upper and lower case text
BIt contains fewer information bits per character than any other code
CIt uses one character as a shift code to send numeric and special characters
DIt includes built in error correction features

42. - E9A14

What is meant by the radiation resistance of an antenna?

SelectAnswer
AThe specific impedance of the antenna
BThe combined losses of the antenna elements and feed line
CThe value of a resistance that would dissipate the same amount of power as that radiated from an antenna
DThe resistance in the atmosphere that an antenna must overcome to be able to radiate a signal

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
AMethod of Moments
BMutual impedance analysis
CCalculus differentiation with respect to physical properties
DGraphical analysis

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

SelectAnswer
A450 ohms
B50 ohms
C72 ohms
D300 ohms

45. - E9D08

What happens as the Q of an antenna increases?

SelectAnswer
AGain is reduced
BSWR bandwidth decreases
CMore common-mode current is present on the feed line
DSWR bandwidth increases

46. - E9E06

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

SelectAnswer
AA series capacitor
BPi-L-network
CPi-network
DA shunt inductor

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AThe same as the characteristic impedance of the transmission line
BVery high impedance
CThe same as the generator output impedance
DVery low impedance

48. - E9G05

What type of chart is shown in Figure E9-3?

SelectAnswer
AElevation angle radiation pattern chart
BAzimuth angle radiation pattern chart
CSmith chart
DFree space radiation directivity chart

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?

SelectAnswer
AIt must be mounted more than 1 wavelength above ground
BIt should be configured as a four-sided loop
CIt should be one or more wavelengths long
DIts overall length must not exceed 1/4 wavelength

50. - E0A01

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

SelectAnswer
ALightning protection
BReduce RFI to telephones and home entertainment systems
CReduce received noise
DReduce RF current flow between pieces of equipment

Figure E6-5

Figure E9-3