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

2. - E1B10

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

SelectAnswer
ASpecific local government channels
BSpecific segments in the amateur service MF, HF, VHF and UHF bands
CAll amateur service frequencies authorized to the control operator
DMilitary Auxiliary Radio System (MARS) channels

3. - E1C04

What is meant by IARP?

SelectAnswer
AAn international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
BAn indication of increased antenna reflected power
CThe internal amateur radio practices policy of the FCC
DA forecast of intermittent aurora radio propagation

4. - E1D01

What is the definition of the term telemetry?

SelectAnswer
AOne-way transmission of measurements at a distance from the measuring instrument
BOne-way transmission that initiates, modifies, or terminates the functions of a device at a distance
CTwo-way single channel transmissions of data
DTwo-way radiotelephone transmissions in excess of 1000 feet

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
BEach General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
CThe procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
DThe prospective VE obtains accreditation from the FCC

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?

SelectAnswer
A420 MHz - 430 MHz
B53 MHz - 54 MHz
C222 MHz - 223 MHz
D440 MHz - 450 MHz

7. - E2A05

What do the letters in a satellite's mode designator specify?

SelectAnswer
AThe location of the ground control station
BThe uplink and downlink frequency ranges
CPower limits for uplink and downlink transmissions
DThe polarization of uplink and downlink signals

8. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

SelectAnswer
ABy scanning lines from left to right in one field and right to left in the next
BBy scanning odd numbered lines in one field and even numbered lines in the next
CBy scanning two fields simultaneously
DBy scanning each field from bottom to top

9. - E2C07

What is the Cabrillo format?

SelectAnswer
AThe most common set of contest rules
BA method of exchanging information during a contest QSO
CThe rules of order for meetings between contest sponsors
DA standard for submission of electronic contest logs

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

SelectAnswer
AJT65
BPACTOR III
CFSK441
DOlivia

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

SelectAnswer
AALE can use any type of control
BRemote
CAutomatic
DLocal

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

SelectAnswer
A2500 miles
B100 miles to 300 miles
C1200 miles
D10 miles to 50 miles

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

SelectAnswer
ATheir polarization is randomly modified
BThey become phase-locked
CThey are bent toward the magnetic poles
DThey become elliptically polarized

14. - E3C01

What does the term ray tracing describe in regard to radio communications?

SelectAnswer
ADetermining the radiation pattern from an array of antennas
BModeling a radio wave's path through the ionosphere
CThe process in which an electronic display presents a pattern
DEvaluating high voltage sources for X-Rays

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

SelectAnswer
AOne-tenth the sample rate
BOne-half the sample rate
CThe same as the sample rate
DIt depends on how the data is stored internally

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

SelectAnswer
A50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
BShort circuit, open circuit, and 50 ohms
CShort circuit, open circuit, and resonant circuit
D50 ohms, 75 ohms, and 90 ohms

17. - E4C08

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

SelectAnswer
AOne-half the maximum sampling buffer size
BThe reference voltage of the analog-to-digital converter
COne-half the maximum sample rate
DThe maximum count value of the analog-to-digital converter

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

SelectAnswer
AThird-order intermodulation produces three products for every input signal within the band of interest
BThird-order products are an indication of poor image rejection
CThe third-order intercept is much higher than other orders
DThe third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E07

How can you determine if line noise interference is being generated within your home?

SelectAnswer
ABy observing the AC power line voltage with a spectrum analyzer
BBy turning off the AC power line main circuit breaker and listening on a battery operated radio
CBy checking the power line voltage with a time domain reflectometer
DBy observing the AC power line waveform with an oscilloscope

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

SelectAnswer
AResistance
BResonance
CConductance
DCapacitance

21. - E5B05

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

SelectAnswer
AIt is unchanged
BThe sign is reversed
CThe magnitude of the susceptance is the reciprocal of the magnitude of the reactance
DIt is shifted by 90 degrees

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

SelectAnswer
APoint 1
BPoint 8
CPoint 5
DPoint 3

23. - E5D15

What is the power factor of an R-L circuit having a 45 degree phase angle between the voltage and the current?

SelectAnswer
A0.866
B0.707
C1.0
D0.5

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

SelectAnswer
ATo provide a voltage reference for the correct amount of reverse-bias gate voltage
BTo keep the gate voltage within specifications and prevent the device from overheating
CTo protect the substrate from excessive voltages
DTo reduce the chance of the gate insulation being punctured by static discharges or excessive voltages

25. - E6B13

What type of bias is required for an LED to emit light?

SelectAnswer
AForward bias
BReverse bias
CZero bias
DInductive bias

26. - E6C01

What is the function of hysteresis in a comparator?

SelectAnswer
ATo cause the output to change states continually
BTo increase the sensitivity
CTo prevent input noise from causing unstable output signals
DTo allow the comparator to be used with AC input signal

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

SelectAnswer
ARF susceptance would increase
BHarmonics and distortion could result
CTemporary changes of the core permeability could result
DMagnetic flux would increase with frequency

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

SelectAnswer
AEnhanced sensitivity to light
BHigh-voltage insulating ability
CTo provide a low-pass frequency response
DBetter dissipation of heat

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

SelectAnswer
AIt becomes unstable
BIt stays the same
CIt decreases
DIt increases

30. - E7A07

What logical operation does a NAND gate perform?

SelectAnswer
AIt produces logic "0" at its output only when all inputs are logic "0"
BIt produces logic "0" at its output only when all inputs are logic "1"
CIt produces logic "1" at its output only when all inputs are logic "1"
DIt produces logic "0" at its output if some but not all inputs are logic "1"

31. - E7B13

In Figure E7-2, what is the purpose of R?

SelectAnswer
ACollector load
BVoltage regulation
CFixed bias
DEmitter load

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D08

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

SelectAnswer
ALinear voltage regulator
BGrounded emitter amplifier
CSwitching voltage regulator
DEmitter follower

34. - E7E07

What is meant by the term baseband in radio communications?

SelectAnswer
AThe frequency components present in the modulating signal
BThe lowest frequency band that the transmitter or receiver covers
CThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
DThe unmodulated bandwidth of the transmitted signal

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

SelectAnswer
ASignal conditioning
BDecimation
CQuadrature mixing
DFast Fourier Transform

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

SelectAnswer
A76
B0.03
C38
D1

37. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
BAn electronic circuit also known as a monostable multivibrator
CAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
DAn electronic circuit consisting of a precision push-pull amplifier with a differential input

38. - E8A06

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

SelectAnswer
A1 to 1
B2.5 to 1
C25 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
A3000
B0.3
C3
D1000

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

SelectAnswer
AIt has more possible states than simple binary
BIt facilitates error detection
CIt increases security
DIt has more resolution than simple binary

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

SelectAnswer
AFaster transmission rate
BSome types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth
CForeign language characters can be sent
DThe signal can overpower interfering signals

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

SelectAnswer
AIt increases arithmetically
BIt is essentially unaffected
CIt increases geometrically
DIt decreases

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

SelectAnswer
A50 degrees
B75 degrees
C30 degrees
D25 degrees

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

SelectAnswer
ABoth the high-angle and low-angle radiation decrease
BThe low-angle radiation decreases
CThe low-angle radiation increases
DThe high-angle radiation increases

45. - E9D04

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

SelectAnswer
ATo swamp out harmonics
BTo minimize the Q
CTo minimize losses
DTo maximize losses

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

SelectAnswer
AReflection coefficient
BDielectric constant
CCharacteristic impedance
DVelocity factor

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 generator output impedance
BThe same as the characteristic impedance of the transmission line
CVery high impedance
DVery low impedance

48. - E9G03

Which of the following is often determined using a Smith chart?

SelectAnswer
ATrigonometric functions
BImpedance and SWR values in transmission lines
CSatellite azimuth and elevation bearings
DBeam headings and radiation patterns

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

SelectAnswer
AAll of these choices are correct
BAtmospheric noise is so high that gain over a dipole is not important
CLow loss coax transmission line is essential for good performance
DThey must be erected at least 1/2 wavelength above the ground to attain good directivity

50. - E0A07

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

SelectAnswer
ABy the yellowish appearance of the gas
BAny ordinary smoke detector can be used
COnly with a carbon monoxide detector
DBy the odor

Figure E5-2

Figure E7-2

Figure E7-3

Figure E7-4

Figure E9-1