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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

SelectAnswer
A170 Hz
B1.5 kHz
C60 Hz
D2.8 kHz

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

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

SelectAnswer
ARepeater and auxiliary stations may not be remotely controlled
BA control operator must be present at the control point
CA control operator need not be present at the control point
DOnly Extra Class operators may be the control operator of a remote station

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

SelectAnswer
AOnly Amateur Extra Class
BOnly General, Advanced or Amateur Extra Class
CAll except Technician Class
DAny class with appropriate operator privileges

5. - E1E12

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

SelectAnswer
AReturn the application document to the examinee
BMaintain the application form with the VEC's records
CDestroy the application form
DSend the application form to the FCC and inform the FCC of the grade

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

SelectAnswer
AIt must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
BIt must be capable of external RF switching between its input and output networks
CIt must exhibit a gain of 0 dB or less over its full output range
DIt must produce full legal output when driven by not more than 5 watts of mean RF input power

7. - E2A09

What do the terms L band and S band specify with regard to satellite communications?

SelectAnswer
AFM and Digital Store-and-Forward systems
BThe 2 meter and 70 centimeter bands
CThe 23 centimeter and 13 centimeter bands
DWhich sideband to use

8. - E2B14

What aspect of an amateur slow-scan television signal encodes the brightness of the picture?

SelectAnswer
ASync amplitude
BTone frequency
CTone amplitude
DSync frequency

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

SelectAnswer
AStore and forward on the 440 MHz band
BSpread spectrum in the 2.4 GHz band
CMultiple Frequency Shift Keying in the 10 GHz band
DFrequency division multiplex in the 24 GHz band

10. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

SelectAnswer
A15 second timed transmission sequences with stations alternating based on location
BAll of these choices are correct
CUse of high speed CW or digital modes
DShort transmission with rapidly repeated call signs and signal reports

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

SelectAnswer
ARTTY
BPSK31
CWinlink
DMFSK

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 MUF is above 30 MHz
CWhen the Moon is at apogee
DWhen the Moon is full

13. - E3B05

Which amateur bands typically support long-path propagation?

SelectAnswer
A30 meters to 10 meters
B6 meters to 2 meters
C160 meters to 10 meters
D160 meters to 40 meters

14. - E3C11

What does VOACAP software model?

SelectAnswer
AVHF radio propagation
BAC voltage and impedance
CHF propagation
DAC current and impedance

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. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A146.52 Hz
B1.4652 MHz
C165.2 Hz
D14.652 kHz

17. - E4C04

How is the noise figure of a receiver defined?

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

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

SelectAnswer
A146.88 MHz and 146.34 MHz
B146.10 MHz and 147.30 MHz
C146.34 MHz and 146.61 MHz
D173.35 MHz and 139.40 MHz

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
BBroadband white noise
CHeterodyne interference
DIgnition noise

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

SelectAnswer
A23.67 kHz
B315.6 Hz
C47.3 kHz
D157.8 Hz

21. - E5B12

What is admittance?

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

22. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

SelectAnswer
AElliptical coordinates
BFaraday grid
CPolar coordinates
DMaidenhead grid

23. - E5D13

How much power is consumed in a circuit consisting of a 100 ohm resistor in series with a 100 ohm inductive reactance drawing 1 ampere?

SelectAnswer
A200 Watts
B141.4 Watts
C70.7 Watts
D100 Watts

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

SelectAnswer
AAlpha rejection frequency
BBeta cutoff frequency
CCorner frequency
DAlpha cutoff frequency

25. - E6B08

Which of the following describes a type of semiconductor diode?

SelectAnswer
AElectrolytic rectifier
BCMOS-field effect
CMetal-semiconductor junction
DThermionic emission diode

26. - E6C07

What best describes a pull-up or pull-down resistor?

SelectAnswer
AA resistor in a keying circuit used to reduce key clicks
BA resistor connected to an op-amp output that only functions when the logic output is false
CA resistor that insures that an oscillator frequency does not drive lower over time
DA resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

SelectAnswer
AStabilizing current
BDirect current
CExcitation current
DMagnetizing current

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

SelectAnswer
A450 ohms
B50 ohms
C300 ohms
D10 ohms

29. - E6F14

Which of the following is true of LCD displays?

SelectAnswer
AThey may be hard view through polarized lenses
BThey only display alphanumeric symbols
CAll of these choices are correct
DThey are hard to view in high ambient light conditions

30. - E7A01

Which is a bi-stable circuit?

SelectAnswer
AAn "OR" gate
BAn "AND" gate
CA clock
DA flip-flop

31. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

SelectAnswer
ATune both the input and output for maximum power
BInstall parasitic suppressors and/or neutralize the stage
CTune the stage for maximum SWR
DUse a phase inverter in the output filter

32. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

SelectAnswer
ATwo capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
BA capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
CAn inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
DTwo inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

SelectAnswer
AA shunt regulator
BA series current source
CA shunt current source
DA series regulator

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

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

SelectAnswer
AAll of these choices are correct
BFIR filters can respond faster to impulses
CFIR filters are easier to implement for a given set of passband rolloff requirements
DFIR filters delay all frequency components of the signal by the same amount

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

SelectAnswer
ARestrict Q but increase gain
BRestrict both gain and Q
CRestrict gain but increase Q
DIncrease both gain and Q

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

SelectAnswer
ABias the crystal at a specified current
BProvide the crystal with a specified parallel capacitance
CBias the crystal at a specified voltage
DProvide the crystal with a specified parallel inductance

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

SelectAnswer
ABy using an absorption wave meter
BBy using a grid dip meter
CBy measuring the heating effect in a known resistor
DBy measuring the voltage with a D'Arsonval meter

39. - E8B11

What is digital time division multiplexing?

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

40. - E8C02

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

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

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

SelectAnswer
A+10 dB
B-30 dB
C+15 dB
D-20 dB

42. - E9A14

What is meant by the radiation resistance of an antenna?

SelectAnswer
AThe resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
BThe combined losses of the antenna elements and feed line
CThe specific impedance of the antenna
DThe value of a resistance that would dissipate the same amount of power as that radiated from an antenna

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

44. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

SelectAnswer
AThe vertical angle increases
BThe lobes align more in the direction of the wire
CThe lobes become more perpendicular to the wire
DThe front-to-back ratio decreases

45. - E9D13

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

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

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 gamma match
BThe delta match
CThe omega match
DThe stub match

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

SelectAnswer
AFoam dielectric has higher velocity factor
BFoam dielectric has lower safe operating voltage limits
CAll of these choices are correct
DFoam dielectric has lower loss per unit of length

48. - E9G03

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

SelectAnswer
ABeam headings and radiation patterns
BImpedance and SWR values in transmission lines
CSatellite azimuth and elevation bearings
DTrigonometric functions

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

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

SelectAnswer
ALocalized heating of the body from RF exposure in excess of the MPE limits
BBlood clotting from the intense magnetic field
CHearing loss caused by high voltage corona discharge
DIngestion of ozone gas from the cooling system