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

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1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

SelectAnswer
ANo, U.S. stations are not permitted to use phone emissions below 3.610 MHz
BNo, the sideband will extend beyond the edge of the phone band segment
CYes, because the displayed frequency is within the 75 meter phone band segment
DYes, because the DX station initiated the contact

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

SelectAnswer
AAt least 43 dB below
BAt least 53 dB below
CAt least 63 dB below
DAt least 73 dB below

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

SelectAnswer
ACEPT agreement
BIARP agreement
CAll of these choices are correct
DITU reciprocal license

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

SelectAnswer
AOnly those of General, Advanced or Amateur Extra Class operators
BAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
COnly those of Amateur Extra Class operators
DAny amateur station, subject to the privileges of the class of operator license held by the control operator

5. - E1E04

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

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

6. - E1F07

When may an amateur station send a message to a business?

SelectAnswer
AWhen the total money involved does not exceed $25
BWhen transmitting international third-party communications
CWhen neither the amateur nor his or her employer has a pecuniary interest in the communications
DWhen the control operator is employed by the FCC or another government agency

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

SelectAnswer
ABecause of the Doppler Effect
BBecause the satellite is spinning
CBecause of the satellite's low orbital altitude
DBecause of ionospheric absorption

8. - E2B06

What is vestigial sideband modulation?

SelectAnswer
ANarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
BSpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
CAmplitude modulation in which one complete sideband and a portion of the other are transmitted
DA type of modulation in which one sideband is inverted

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.?

SelectAnswer
ANo additional indicator is required
B/ followed by the USPS two letter abbreviation for the state in which the remote station is located
C/R# where # is the district of the remote station
DThe ARRL section of the remote station

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

SelectAnswer
ALatitude and longitude
BTime and frequency
CPolar coordinates
DRadio direction finding spectrum analysis

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

SelectAnswer
AForward Error Correction
BFinal Error Correction
CFirst Error Correction
DFatal Error Correction

12. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

SelectAnswer
A5000 miles, if the Moon is at perigee
B12,000 miles, if the Moon is visible by both stations
C500 miles, if the Moon is at perigee
D2000 miles, if the Moon is at apogee

13. - E3B13

Why is chordal hop propagation desirable?

SelectAnswer
AThe signal experiences less loss along the path compared to normal skip propagation
BSignals travel faster along ionospheric chords
CAtmospheric noise is lower in the direction of chordal hop propagation
DThe MUF for chordal hop propagation is much lower than for normal skip propagation

14. - E3C02

What is indicated by a rising A or K index?

SelectAnswer
AAn increase in the critical frequency
BDecreasing disruption of the geomagnetic field
CIncreasing disruption of the geomagnetic field
DHigher levels of solar UV radiation

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

SelectAnswer
AIt does not require an expensive high-precision time base
BIt provides improved resolution of low-frequency signals within a comparable time period
CIt can directly measure the modulation index of an FM transmitter
DIt can run on battery power for remote measurements

16. - E4B07

What do the subscripts of S parameters represent?

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

17. - E4C10

Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?

SelectAnswer
A300 Hz
B2400 Hz
C100 Hz
D6000 Hz

18. - E4D13

Which of the following can cause receiver desensitization?

SelectAnswer
AAudio bias adjusted too high
BAudio gain adjusted too low
CSquelch gain misadjusted
DStrong adjacent channel signals

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

SelectAnswer
AAll of these choices are correct
BIgnition noise
CBroadband white noise
DHeterodyne interference

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

SelectAnswer
A1.78 MHz
B44.72 MHz
C3.56 MHz
D22.36 MHz

21. - E5B13

What letter is commonly used to represent susceptance?

SelectAnswer
AG
BX
CB
DY

22. - E5C12

If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?

SelectAnswer
AIt contains resistance and capacitive reactance
BIt contains resistance and inductive reactance
CIt is equivalent to a pure resistance
DIt has to be a direct current circuit

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

SelectAnswer
A200 watts
B600 watts
C1600 watts
D1000 watts

24. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

SelectAnswer
ABase-to-emitter resistance of approximately 6 to 7 ohms
BBase-to-emitter voltage of approximately 0.6 to 0.7 volts
CBase-to-emitter voltage of approximately 6 to 7 volts
DBase-to-emitter resistance of approximately 0.6 to 0.7 ohms

25. - E6B13

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

SelectAnswer
AForward bias
BInductive bias
CReverse bias
DZero bias

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

SelectAnswer
AThe comparator enters latch-up
BThe IC input can be damaged
CThe feedback loop becomes unstable
DThe comparator changes its output state

27. - E6D16

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

SelectAnswer
AFeedback capacitor
BTrimmer capacitor
CClipper capacitor
DSnubber capacitor

28. - E6E12

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

SelectAnswer
AEnhanced sensitivity to light
BTo provide a low-pass frequency response
CBetter dissipation of heat
DHigh-voltage insulating ability

29. - E6F09

What is the efficiency of a photovoltaic cell?

SelectAnswer
AThe effective payback period
BThe open-circuit voltage divided by the short-circuit current under full illumination
CThe relative fraction of light that is converted to current
DThe output RF power divided by the input DC power

30. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
AAssertive Logic
BPositive Logic
CReverse Logic
DNegative logic

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

SelectAnswer
ASignal distortion and excessive bandwidth
BIncreased overall intelligibility
CReduced intermodulation products
DSignal inversion

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

SelectAnswer
APi
BOmega
CCascode
DPi-L

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

SelectAnswer
AIt eliminates the need for a pass transistor
BIt has a ramp voltage as its output
CThe control element duty cycle is proportional to the line or load conditions
DThe conduction of a control element is varied to maintain a constant output voltage

34. - E7E06

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

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

35. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

SelectAnswer
ASample clock phase noise
BProcessor latency
CSample width in bits
DSample rate

36. - E7G03

What is the typical input impedance of an integrated circuit op-amp?

SelectAnswer
A100 ohms
BVery high
C1000 ohms
DVery low

37. - E7H02

Which describes a microphonic?

SelectAnswer
ADistortion caused by RF pickup on the microphone cable
BAn IC used for amplifying microphone signals
CChanges in oscillator frequency due to mechanical vibration
DExcess loading of the microphone by an oscillator

38. - E8A02

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

SelectAnswer
AA sawtooth wave
BA square wave
CA cosine wave
DA sine wave

39. - E8B09

What is meant by deviation ratio?

SelectAnswer
AThe ratio of the highest audio modulating frequency to the average audio modulating frequency
BThe ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
CThe ratio of the audio modulating frequency to the center carrier frequency
DThe ratio of the carrier center frequency to the audio modulating frequency

40. - E8C11

What is the relationship between symbol rate and baud?

SelectAnswer
ASymbol rate is only used for packet-based modes
BBaud is twice the symbol rate
CBaud is only used for RTTY
DThey are the same

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

SelectAnswer
AHarmonics on higher bands
BStrong ALC action
CRapid signal fading
DHigh reflected power

42. - E9A09

How is antenna efficiency calculated?

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

43. - E9B01

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

SelectAnswer
A30 degrees
B25 degrees
C75 degrees
D50 degrees

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

SelectAnswer
AIt changes the impedance angle of the matching network
BIt causes increased SWR
CIt reduces low-angle radiation
DIt reduces losses in the radiating portion of the antenna

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

SelectAnswer
AIt is too sharply directional at lower frequencies
BIt must be neutralized
CIt radiates the harmonics and fundamental equally well
DIt might radiate harmonics

46. - E9E12

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

SelectAnswer
AIt makes sure the antenna has a low-angle radiation pattern
BIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
CIt allows single-band antennas to operate on other bands
DIt ensures that each driven element operates in concert with the others to create the desired antenna pattern

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
BThe same as the generator output impedance
CVery high impedance
DVery low impedance

48. - E9G01

Which of the following can be calculated using a Smith chart?

SelectAnswer
AAntenna radiation pattern
BImpedance along transmission lines
CRadio propagation
DRadiation resistance

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

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

SelectAnswer
AAll of the choices are correct
BUse an antenna modeling program to calculate field strength at accessible locations
CUse a hand calculator plus Smith-chart equations to calculate the fields
DUse a calibrated antenna analyzer

Figure E9-1