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

2. - E1B09

Which amateur stations may be operated under RACES rules?

SelectAnswer
AAny FCC-licensed amateur station certified by the responsible civil defense organization for the area served
BAny FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
CAny FCC-licensed amateur station except a Technician class
DOnly those club stations licensed to Amateur Extra class operators

3. - E1C04

What is meant by IARP?

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

4. - E1D04

What is an Earth station in the amateur satellite service?

SelectAnswer
AAn amateur station that is not able to communicate using amateur satellites
BAn amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
CAny amateur station on the surface of the Earth
DAn amateur station that transmits telemetry consisting of measurement of upper atmosphere

5. - E1E03

What is a Volunteer Examiner Coordinator?

SelectAnswer
AAn organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
BA person who has volunteered to prepare amateur operator license examinations
CThe person who has entered into an agreement with the FCC to be the VE session manager
DA person who has volunteered to administer amateur operator license examinations

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

7. - E2A13

What type of satellite appears to stay in one position in the sky?

SelectAnswer
AHEO
BGeostationary
CGeomagnetic
DLEO

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

SelectAnswer
AThe vestigial sideband contains chroma information
BVestigial sideband reduces bandwidth while allowing for simple video detector circuitry
CVestigial sideband provides high frequency emphasis to sharpen the picture
DThe vestigial sideband carries the audio information

9. - E2C07

What is the Cabrillo format?

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

10. - E2D08

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

SelectAnswer
AUnnumbered Information
BAcknowledgement
CDisconnect
DConnect

11. - E2E03

How is the timing of JT65 contacts organized?

SelectAnswer
AIt depends on the lunar phase
BStations take turns on alternate days
CBy exchanging ACK/NAK packets
DAlternating transmissions at 1 minute intervals

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

SelectAnswer
AWarm and cold fronts
BLightning discharges
CGray-line
DSprites and jets

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

SelectAnswer
AAny time
BAround sunset
CAround sunrise
DEarly evening

14. - E3C15

What might a sudden rise in radio background noise indicate?

SelectAnswer
AA solar flare has occurred
BLong-path propagation is occurring
CIncreased transequatorial propagation likely
DA meteor ping

15. - E4A15

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

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

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

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

SelectAnswer
AFrequency discrimination
BDesensitization
CCapture effect
DCross-modulation interference

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

SelectAnswer
AAmplifier desensitization
BNeutralization
CAdjacent channel interference
DIntermodulation interference

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

SelectAnswer
ADifferential-mode current
BReturn current
CReactive current only
DCommon-mode current

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

SelectAnswer
AIt equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance
BIt is at a minimum
CIt is at a maximum
DIt equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

SelectAnswer
AOne discharge period
BAn exponential discharge rate of one
CA discharge factor of one
DOne time constant

22. - E5C06

What does the impedance 50-j25 represent?

SelectAnswer
A25 ohms resistance in series with 50 ohms inductive reactance
B50 ohms resistance in series with 25 ohms inductive reactance
C50 ohms resistance in series with 25 ohms capacitive reactance
D25 ohms resistance in series with 50 ohms capacitive reactance

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

SelectAnswer
A0.577
B0.5
C0.866
D1.73

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 reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
CTo protect the substrate from excessive voltages
DTo keep the gate voltage within specifications and prevent the device from overheating

25. - E6B09

What is a common use for point contact diodes?

SelectAnswer
AAs a high voltage rectifier
BAs a constant current source
CAs an RF detector
DAs a constant voltage source

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
ALower distortion
BDifferential output capability
CImmune to damage from static discharge
DLower power consumption

27. - E6D08

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

SelectAnswer
APowdered-iron cores use smaller diameter wire for the same inductance
BPowdered-iron cores generally maintain their characteristics at higher currents
CPowdered-iron cores generally have greater initial permeability
DPowdered-iron cores generally require fewer turns to produce a given inductance

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

SelectAnswer
AGround-plane construction
BWave-soldering construction
CPoint-to-point construction
DMicrostrip construction

29. - E6F05

Which describes an optical shaft encoder?

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

30. - E7A08

What logical operation does an OR gate perform?

SelectAnswer
AIt produces logic "0" at its output if all inputs are logic "1"
BIt only produces logic "0" at its output when all inputs are logic "1"
CIt produces logic "1" at its output if any or all inputs are logic "1"
DIt produces logic "1" at its output if all inputs are logic "0"

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

SelectAnswer
AAll of these choices are correct
BCreation of parasitic oscillations
CLow efficiency
DTransmission of spurious signals

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

SelectAnswer
AA notch filter
BA Pi-network filter
CAn all-pass filter
DA band-pass filter

33. - E7D08

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

SelectAnswer
ASwitching voltage regulator
BGrounded emitter amplifier
CLinear voltage regulator
DEmitter follower

34. - E7E01

Which of the following can be used to generate FM phone emissions?

SelectAnswer
AA reactance modulator on the final amplifier
BA balanced modulator on the oscillator
CA balanced modulator on the audio amplifier
DA reactance modulator on the oscillator

35. - E7F12

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

SelectAnswer
ASignal conditioning
BDecimation
CFast Fourier Transform
DQuadrature mixing

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
A24
B94
C47
D0.21

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a neutralizing capacitor
CThrough link coupling
DThrough a quartz crystal

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

SelectAnswer
ALevel shifting
BHarmonic regeneration
CPhase reversal
DSequential sampling

39. - E8B11

What is digital time division multiplexing?

SelectAnswer
ATwo or more signals are quadrature modulated to increase bandwidth efficiency
BTwo or more signals are arranged to share discrete time slots of a data transmission
CTwo or more data streams share the same channel by transmitting time of transmission as the sub-carrier
DTwo or more data streams are assigned to discrete sub-carriers on an FM transmitter

40. - E8C06

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

SelectAnswer
A1.0 kHz
B0.1 Hz
C0.3 kHz
D0.5 kHz

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
BBaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
CBaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
DBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A02

What antenna has no gain in any direction?

SelectAnswer
AQuarter-wave vertical
BYagi
CIsotropic antenna
DHalf-wave dipole

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

SelectAnswer
AMeasure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
BNote the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference
CDraw two imaginary lines through the ends of the elements and measure the angle between the lines
DMeasure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna

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
AA Figure-8 broadside to the axis of the array
BOmni-directional
CA Figure-8 end-fire along the axis of the array
DCardioid

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

SelectAnswer
AThe SWR is reduced
BThe frequency response is widened over the whole frequency band
CThe front-to-back ratio decreases
DThe front-to-back ratio increases

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

SelectAnswer
AAll of these choices are correct
BDouble-bazooka match
CGamma match
DHairpin match

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AAn inductive reactance
BThe same as the characteristic impedance of the line
CA capacitive reactance
DThe same as the input impedance to the final generator stage

48. - E9G03

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

SelectAnswer
AImpedance and SWR values in transmission lines
BSatellite azimuth and elevation bearings
CBeam headings and radiation patterns
DTrigonometric functions

49. - E9H08

What is the function of a sense antenna?

SelectAnswer
AIt allows DF antennas to receive signals at different vertical angles
BIt modifies the pattern of a DF antenna array to provide a null in one direction
CIt provides diversity reception that cancels multipath signals
DIt increases the sensitivity of a DF antenna array

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

SelectAnswer
ABeryllium Oxide
BZinc oxide
CUranium Hexafluoride
DMica

Figure E7-3

Figure E7-4