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

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

SelectAnswer
A100 watts PEP effective radiated power relative to the gain of a half-wave dipole
B50 watts PEP effective radiated power relative to an isotropic radiator
C100 watts PEP effective radiated power relative to an isotropic radiator
D50 watts PEP effective radiated power relative to a dipole

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C02

What is meant by automatic control of a station?

SelectAnswer
AThe use of devices and procedures for control so that the control operator does not have to be present at a control point
BThe use of a control link between a control point and a locally controlled station
CRemotely controlling a station's antenna pattern through a directional control link
DA station operating with its output power controlled automatically

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

SelectAnswer
A2 meters
B6 meters and 2 meters
C2 meters and 1.25 meters
D6 meters, 2 meters, and 1.25 meters

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

SelectAnswer
A4
B3
C5
D2

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

SelectAnswer
AAll of these choices are correct
BA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
CThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
DThe transmission must not be used to obscure the meaning of any communication

7. - E2A13

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

SelectAnswer
AGeomagnetic
BLEO
CHEO
DGeostationary

8. - E2B18

On which of the following frequencies is one likely to find FM ATV transmissions?

SelectAnswer
A14.230 MHz
B52.525 MHz
C29.6 MHz
D1255 MHz

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

SelectAnswer
AIn the middle of each band, usually on the national calling frequency
BIn the middle of the band, usually 25 kHz above the national calling frequency
CAt the top of each band, usually in a segment reserved for contests
DIn the weak signal segment of the band, with most of the activity near the calling frequency

10. - E2D07

What digital protocol is used by APRS?

SelectAnswer
APACTOR
B802.11
CAX.25
DAMTOR

11. - E2E03

How is the timing of JT65 contacts organized?

SelectAnswer
ABy exchanging ACK/NAK packets
BAlternating transmissions at 1 minute intervals
CIt depends on the lunar phase
DStations take turns on alternate days

12. - E3A11

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

SelectAnswer
A10 miles to 50 miles
B1200 miles
C100 miles to 300 miles
D2500 miles

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

SelectAnswer
A10 meters
B6 meters
C80 meters
D20 meters

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

SelectAnswer
ADownward bending due to density variations in the atmosphere
BDownward bending due to aurora refraction
CE-region skip
DD-region skip

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

SelectAnswer
ASampling rate
BInput capacitance
CInput impedance
DSample resolution

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A1.4652 kHz
B0.1 MHz
C1.4652 Hz
D14.652 Hz

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

SelectAnswer
A1 kHz
B4.2 kHz
C4.8 kHz
D2.4 kHz

18. - E4D02

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

SelectAnswer
AOscillator instability and severe audio distortion of all but the strongest received signals
BOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
CCross-modulation of the desired signal and desensitization from strong adjacent 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
AAll of these choices are correct
BThe interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
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. - E5A02

What is resonance in an electrical circuit?

SelectAnswer
AThe frequency at which the reactive impedance equals the resistive impedance
BThe frequency at which the capacitive reactance equals the inductive reactance
CThe lowest frequency that will pass current
DThe highest frequency that will pass current

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
A14 degrees with the voltage lagging the current
B76 degrees with the voltage lagging the current
C14 degrees with the voltage leading the current
D76 degrees with the voltage leading the current

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

SelectAnswer
AResistive component
BThe difference between the resistive and reactive components
CReactive component
DThe sum of the reactive and resistive components

23. - E5D05

Which parasitic characteristic increases with conductor length?

SelectAnswer
APermittivity
BMalleability
CInductance
DPermeability

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

SelectAnswer
AAn FET has high input impedance; a bipolar transistor has low input impedance
BAn FET has low input impedance; a bipolar transistor has high input impedance
CThey are both low impedance
DThey are both high impedance

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C12

What is BiCMOS logic?

SelectAnswer
AA logic device with two CMOS circuits per package
BA FET logic family based on bimetallic semiconductors
CAn integrated circuit logic family using both bipolar and CMOS transistors
DA logic family based on bismuth CMOS devices

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

SelectAnswer
APolystyrene and polyethylene
BFerrite and brass
CCobalt and aluminum
DTeflon and Delrin

28. - E6E07

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

SelectAnswer
APoint-to-point construction
BMicrostrip construction
CGround-plane construction
DWave-soldering construction

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

SelectAnswer
AAn amplitude modulated helium-neon laser
BA lens and a photomultiplier
CA frequency modulated helium-neon laser
DAn LED and a phototransistor

30. - E7A12

What type of logic defines "0" as a high voltage?

SelectAnswer
AReverse Logic
BNegative logic
CPositive Logic
DAssertive Logic

31. - E7B11

In Figure E7-1, what is the purpose of R3?

SelectAnswer
AOutput load resistor
BSelf bias
CEmitter bypass
DFixed bias

32. - E7C15

What is a crystal lattice filter?

SelectAnswer
AA power supply filter made with interlaced quartz crystals
BAn audio filter made with four quartz crystals that resonate at 1kHz intervals
CA filter with narrow bandwidth and steep skirts made using quartz crystals
DA filter with wide bandwidth and shallow skirts made using quartz crystals

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

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

34. - E7E03

How does an analog phase modulator function?

SelectAnswer
ABy varying the tuning of a microphone preamplifier to produce AM signals
BBy varying the tuning of a microphone preamplifier to produce PM signals
CBy varying the tuning of an amplifier tank circuit to produce AM signals
DBy varying the tuning of an amplifier tank circuit to produce PM signals

35. - E7F08

What is the function of decimation with regard to digital filters?

SelectAnswer
ARemoving unnecessary significant digits
BReducing the effective sample rate by removing samples
CConverting data to binary code decimal form
DAttenuating the signal

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

SelectAnswer
A-2.3 volts
B-0.23 volts
C2.3 volts
D0.23 volts

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

SelectAnswer
ATaft, Pierce and negative feedback
BTaft, Hartley and Pierce
CPierce, Fenner and Beane
DColpitts, Hartley and Pierce

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

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

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
A1000
B3000
C3
D0.3

40. - E8C02

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

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

41. - E8D06

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

SelectAnswer
ARapid signal fading
BStrong ALC action
CHarmonics on higher bands
DHigh reflected power

42. - E9A07

What is meant by antenna gain?

SelectAnswer
AThe final amplifier gain minus the transmission line losses
BThe ratio of the signal in the forward direction to that in the opposite direction
CThe ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
DThe ratio of the amount of power radiated by an antenna compared to the transmitter output power

43. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below the guideline of 10 segments per half-wavelength?

SelectAnswer
AThe resulting design will favor radiation of harmonic energy
BThe antenna will become mechanically unstable
CThe computed feed point impedance may be incorrect
DGround conductivity will not be accurately modeled

44. - E9C13

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

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

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

SelectAnswer
ATo lower the losses
BTo increase the SWR bandwidth
CTo cancel capacitive reactance
DTo lower the Q

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

SelectAnswer
APi-network
BA shunt inductor
CPi-L-network
DA series capacitor

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

SelectAnswer
A10 meters
B71 meters
C20 meters
D15 meters

48. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
APoints with constant resistance
BSWR
CFrequency
DPoints with constant reactance

49. - E9H06

What is the triangulation method of direction finding?

SelectAnswer
AAntenna headings from several different receiving locations are used to locate the signal source
BThe geometric angles of sky waves from the source are used to determine its position
CA fixed receiving station plots three headings to the signal source
DA fixed receiving station uses three different antennas to plot the location of the signal source

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

SelectAnswer
AThe high gain antennas commonly used can result in high exposure levels
BThe extremely high frequency energy can damage the joints of antenna structures
CMicrowaves often travel long distances by ionospheric reflection
DMicrowaves are ionizing radiation

Figure E7-1

Figure E7-4