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

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

SelectAnswer
AAn Environmental Assessment must be submitted to the FCC
BA letter of intent must be filed with the National Audubon Society
CA form FSD-15 must be submitted to the Department of the Interior
DA proposal must be submitted to the National Park Service

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

SelectAnswer
AMessages intended for connection to users of the maritime satellite service
BBusiness-related messages for non-profit organizations
CAll of these choices are correct
DCommunications incidental to the purpose of the amateur service and remarks of a personal nature

4. - E1D03

What is a telecommand station in the amateur satellite service?

SelectAnswer
AAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
BAn amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
CAn amateur station located more than 50 km above the Earth's surface
DAn amateur station that transmits telemetry consisting of measurements of upper atmosphere

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

SelectAnswer
AA fine of up to $1000 per occurrence
BA sentence of up to one year in prison
CRevocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
DAll of these choices are correct

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

SelectAnswer
AOnly on amateur frequencies above 222 MHz
BOnly on amateur frequencies above 420 MHz
COnly on amateur frequencies above 50 MHz
DOnly on amateur frequencies above 144 MHz

7. - E2A12

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

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

8. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

SelectAnswer
A90
B30
C60
D120

9. - E2C07

What is the Cabrillo format?

SelectAnswer
AA standard for submission of electronic contest logs
BThe most common set of contest rules
CA method of exchanging information during a contest QSO
DThe rules of order for meetings between contest sponsors

10. - E2D07

What digital protocol is used by APRS?

SelectAnswer
A802.11
BAX.25
CPACTOR
DAMTOR

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

SelectAnswer
APSK31
BMT63
CRTTY
DPACTOR

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

SelectAnswer
AWhen the Moon is at perigee
BWhen the Moon is at apogee
CWhen the Moon is full
DWhen the MUF is above 30 MHz

13. - E3B07

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

SelectAnswer
AMeteor scatter
BHigh D layer absorption
CTransmit frequency is higher than the MUF
DReceipt of a signal by more than one path

14. - E3C11

What does VOACAP software model?

SelectAnswer
AAC current and impedance
BHF propagation
CVHF radio propagation
DAC voltage and impedance

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 can run on battery power for remote measurements
CIt provides improved resolution of low-frequency signals within a comparable time period
DIt can directly measure the modulation index of an FM transmitter

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

SelectAnswer
AThere is more power going into the antenna
BThere is an impedance mismatch between the antenna and feed line
CThere is possibly a short to ground in the feed line
DThe transmitter is not properly neutralized

17. - E4C04

How is the noise figure of a receiver defined?

SelectAnswer
AThe ratio in dB of the noise generated by the receiver to the theoretical minimum noise
BThe ratio of thermal noise to atmospheric noise
CThe ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network
DThe ratio of atmospheric noise to phase noise

18. - E4D13

Which of the following can cause receiver desensitization?

SelectAnswer
AAudio bias adjusted too high
BSquelch gain misadjusted
CStrong adjacent channel signals
DAudio gain adjusted too low

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
ATying all ground connections to a common point resulting in differential mode currents in the shield
BLow inductance ground connections at both ends of the shield
CCommon mode currents on the shield and conductors
DUse of braided shielding material

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
A3.56 MHz
B1.78 MHz
C44.72 MHz
D22.36 MHz

21. - E5B12

What is admittance?

SelectAnswer
AThe turns ratio of a transformer
BThe term for the gain of a field effect transistor
CThe inverse of impedance
DThe unit used for Q factor

22. - E5C03

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

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

23. - E5D05

Which parasitic characteristic increases with conductor length?

SelectAnswer
APermeability
BInductance
CMalleability
DPermittivity

24. - E6A17

What are the names of the three terminals of a field-effect transistor?

SelectAnswer
AEmitter, base, collector
BGate, drain, source
CGate 1, gate 2, drain
DEmitter, base 1, base 2

25. - E6B05

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

SelectAnswer
AAbility to dissipate large amounts of power
BA large region of intrinsic material
CExtremely high reverse breakdown voltage
DReverse bias controls its forward voltage drop

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

SelectAnswer
AMany similar gates are less expensive than a mixture of gate types
BAll of these choices are correct
CComplex logic functions can be created in a single integrated circuit
DA PGA contains its own internal power supply

27. - E6D17

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

SelectAnswer
AMagnetic flux would increase with frequency
BHarmonics and distortion could result
CRF susceptance would increase
DTemporary changes of the core permeability could result

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

SelectAnswer
AIts phase shift changes rapidly with frequency
BIt is a CMOS analog-to-digital converter
CIt is used in a battery charger circuit
DIt samples an analog signal and passes it in stages from the input to the output

29. - E6F02

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

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

30. - E7A01

Which is a bi-stable circuit?

SelectAnswer
AA flip-flop
BAn "AND" gate
CAn "OR" gate
DA clock

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
AIncreased overall intelligibility
BSignal distortion and excessive bandwidth
CSignal inversion
DReduced intermodulation products

32. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with extreme stop band ripple
BExtremely flat response over its pass band with gradually rounded stop band corners
CGradual passband rolloff with minimal 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
AGrounded emitter amplifier
BEmitter follower
CLinear voltage regulator
DSwitching voltage regulator

34. - E7E02

What is the function of a reactance modulator?

SelectAnswer
ATo produce PM signals by using an electrically variable inductance or capacitance
BTo produce AM signals by using an electrically variable inductance or capacitance
CTo produce PM signals by using an electrically variable resistance
DTo produce AM signals by using an electrically variable resistance

35. - E7F01

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

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

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

SelectAnswer
A47
B94
C0.21
D24

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

SelectAnswer
AA hybrid synthesizer
BA diode-switching matrix synthesizer
CA phase locked loop synthesizer
DA direct digital synthesizer

38. - E8A11

What type of information can be conveyed using digital waveforms?

SelectAnswer
AAll of these choices are correct
BData
CVideo signals
DHuman speech

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

SelectAnswer
AA frequency modulation technique which uses non-harmonically related frequencies
BA digital mode for narrow band, slow speed transmissions
CA digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
DA bandwidth compression technique using Fourier transforms

40. - E8C06

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

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

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
AFrequency hopping
BBinary phase-shift keying
CPhase compandored spread spectrum
DDirect sequence

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

SelectAnswer
ATo measure the near-field radiation density from a transmitting antenna
BTo calculate the front-to-back ratio of the antenna
CTo match impedances in order to minimize standing wave ratio on the transmission line
DTo calculate the front-to-side ratio of the antenna

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

SelectAnswer
A3 dB
B28 dB
C24 dB
D15 dB

44. - E9C11

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

SelectAnswer
AThe high-angle radiation increases
BThe low-angle radiation increases
CBoth the high-angle and low-angle radiation decrease
DThe low-angle radiation decreases

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

SelectAnswer
AIt is increased
BIt is decreased
CNo change occurs
DIt becomes flat

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

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

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

SelectAnswer
A20 meters
B0.2 meters
C3.5 meters
D2.3 meters

48. - E9G05

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

SelectAnswer
AAzimuth angle radiation pattern chart
BSmith chart
CElevation angle radiation pattern chart
DFree space radiation directivity chart

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

SelectAnswer
AIt narrows the bandwidth of the received signal to improve signal to noise ratio
BIt compensates for the effects of an isotropic antenna, thereby improving directivity
CIt prevents receiver overload which could make it difficult to determine peaks or nulls
DIt reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity

50. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

SelectAnswer
APolymorphic silicon
BPolytetrafluroethylene
CPolyethylene
DPolychlorinated Biphenyls

Figure E7-3

Figure E7-4

Figure E9-2

Figure E9-3