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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

SelectAnswer
ANo, U.S. stations are not permitted to use phone emissions above 14.340 MHz
BNo, the sideband will extend beyond the band edge
CYes, because you were not the station calling CQ
DYes, because the displayed frequency is within the 20 meter band

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 73 dB below
DAt least 63 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. - E1D02

What is the amateur satellite service?

SelectAnswer
AA radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
BA spacecraft launching service for amateur-built satellites
CA radio communications service using stations on Earth satellites for public service broadcast
DA radio communications service using amateur radio stations on satellites

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

SelectAnswer
ASend the application form to the FCC and inform the FCC of the grade
BMaintain the application form with the VEC's records
CReturn the application document to the examinee
DDestroy the application form

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

SelectAnswer
AIt was imported from a manufacturer in another country and was certificated by that country's government
BIt was imported from a manufacturer in a country that does not require certification of RF power amplifiers
CThe equipment dealer assembled it from a kit
DIt was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station

7. - E2A01

What is the direction of an ascending pass for an amateur satellite?

SelectAnswer
AFrom east to west
BFrom north to south
CFrom west to east
DFrom south to north

8. - E2B06

What is vestigial sideband modulation?

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

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

SelectAnswer
AThe acceptable practice of manually posting the call signs of stations on a spotting network
BA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
CThe generally prohibited practice of posting one's own call sign and frequency on a spotting network
DAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
ADisconnect
BAcknowledgement
CUnnumbered Information
DConnect

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

SelectAnswer
AThe receiver has drifted 5 kHz from the desired receive frequency
BThe mark and space signal have been inverted
CSelective fading has occurred
DOne of the signal filters is saturated

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. - E3B07

Which of the following could account for hearing an echo on the received signal of a distant station?

SelectAnswer
ATransmit frequency is higher than the MUF
BReceipt of a signal by more than one path
CHigh D layer absorption
DMeteor scatter

14. - E3C13

What type of polarization is best for ground-wave propagation?

SelectAnswer
ACircular
BVertical
CHorizontal
DElliptical

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

SelectAnswer
AA frequency standard is displayed and the probe is adjusted until the deflection time is accurate
BA high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
CA square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
DA DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A10 Hz
B1465.20 Hz
C146.52 kHz
D146.52 Hz

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

SelectAnswer
A13.845 MHz
B14.755 MHz
C15.210 MHz
D14.445 MHz

18. - E4D02

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

SelectAnswer
AOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
BCross-modulation of the desired signal and desensitization from strong adjacent signals
COscillator instability and severe audio distortion of all but the strongest received signals
DCross-modulation of the desired signal and insufficient audio power to operate the speaker

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

SelectAnswer
AThe interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
BAll of these choices are correct
CThe interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
DThe interfering signal may drift slowly across the HF spectrum

20. - E5A16

What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?

SelectAnswer
A7.12 kHz
B7.12 MHz
C23.5 kHz
D23.5 MHz

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

SelectAnswer
A76 degrees with the voltage lagging the current
B14 degrees with the voltage lagging the current
C76 degrees with the voltage leading the current
D14 degrees with the voltage leading the current

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

SelectAnswer
ANear field diagram
BFar field diagram
CVenn diagram
DPhasor diagram

23. - E5D14

What is reactive power?

SelectAnswer
APower consumed in circuit Q
BPower lost because of capacitor leakage
CPower consumed in wire resistance in an inductor
DWattless, nonproductive power

24. - E6A07

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

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

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

SelectAnswer
ATunnel
BJunction
CZener
DPoint contact

26. - E6C08

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

SelectAnswer
A1
B3
C4
D2

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

SelectAnswer
AFerrite toroids are easier to use with surface mount technology
BFerrite toroids generally require fewer turns to produce a given inductance value
CFerrite toroids generally have lower initial permeability
DFerrite toroids generally have better temperature stability

28. - E6E11

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

SelectAnswer
ALow leakage doubly insulated package
BTwo chips in each package (Dual In Package)
CA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
DPackage mounts in a direct inverted position

29. - E6F05

Which describes an optical shaft encoder?

SelectAnswer
AA device which detects rotation of a control by interrupting a light source with a patterned wheel
BA device which measures the strength of a beam of light using analog to digital conversion
CA device for generating RTTY signals by means of a rotating light source
DA digital encryption device often used to encrypt spacecraft control signals

30. - E7A02

What is the function of a decade counter digital IC?

SelectAnswer
AIt produces one output pulse for every ten input pulses
BIt produces ten output pulses for every input pulse
CIt decodes a decimal number for display on a seven segment LED display
DIt adds two decimal numbers together

31. - E7B13

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

SelectAnswer
AVoltage regulation
BCollector load
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 sharp cutoff with one or more notches in the stop band
CExtremely flat response over its pass band with gradually rounded stop band corners
DGradual passband rolloff with extreme stop band ripple

33. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-3?

SelectAnswer
ATo self-resonate at the hum frequency
BIt is a brute force filter for the output
CTo provide fixed DC bias for Q1
DIt bypasses hum around D1

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

SelectAnswer
AA beat frequency is generated
BAutomatic limiting occurs
CMixer blanking occurs
DSpurious mixer products are generated

35. - E7F07

What function can a Fast Fourier Transform perform?

SelectAnswer
AConverting 8-bit data to 16 bit data
BConverting analog signals to digital form
CConverting digital signals from the time domain to the frequency domain
DConverting digital signals to analog form

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

SelectAnswer
AAs an audio filter in a receiver
BFor smoothing power supply output
CAs a high-pass filter used to block RFI at the input to receivers
DAs a low-pass filter used between a transmitter and a transmission line

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

SelectAnswer
ABroadband noise
BSpurious signals at discrete frequencies
CDigital conversion noise
DNyquist limit noise

38. - E8A06

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

SelectAnswer
A100 to 1
B25 to 1
C2.5 to 1
D1 to 1

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AEME
BHigh speed digital modes
CExtremely low-power contacts
DOFDM signals are not allowed on amateur bands

40. - E8C02

What is the definition of symbol rate in a digital transmission?

SelectAnswer
AThe rate at which the waveform of a transmitted signal changes to convey information
BThe number of characters carried per second by the station-to-station link
CThe duration of each bit in a message sent over the air
DThe number of control characters in a message packet

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

SelectAnswer
AIf interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
BA pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
CIf interference is detected by the receiver it will signal the transmitter to change frequencies
DThe frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

SelectAnswer
A3.85 dB
B6.0 dB
C8.15 dB
D2.79 dB

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

SelectAnswer
A18 dB
B14 dB
C36 dB
D24 dB

44. - E9C03

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

SelectAnswer
AOmni-directional
BA Figure-8 broadside to the axis of the array
CA Figure-8 end-fire along the axis of the array
DCardioid

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
AA resistive wire, such as spark plug wire
BA cable with six or seven 18 gauge conductors in parallel
CA wide flat copper strap
DA single 12 gauge or 10 gauge stainless steel wire

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

SelectAnswer
AThe epsilon match
BThe gamma match
CThe stub match
DThe delta match

47. - E9F14

What impedance does a 1/2 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 line
BThe same as the output impedance of the generator
CVery low impedance
DVery high impedance

48. - E9G05

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

SelectAnswer
AAzimuth angle radiation pattern chart
BSmith chart
CFree space radiation directivity chart
DElevation angle radiation pattern chart

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

SelectAnswer
AIt is electro statically balanced against ground, giving better nulls
BIt allows stations to communicate without giving away their position
CIt eliminates tracking errors caused by strong out-of-band signals
DIt automatically cancels ignition noise in mobile installations

50. - E0A07

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

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

Figure E6-5

Figure E7-2

Figure E7-3

Figure E9-1

Figure E9-3