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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
B100 watts PEP effective radiated power relative to an isotropic radiator
C50 watts PEP effective radiated power relative to an isotropic radiator
D50 watts PEP effective radiated power relative to a dipole

2. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AAny transmitted signal that unintentionally interferes with another licensed radio station
BAn amateur station transmission made at random without the proper call sign identification
CA signal transmitted to prevent its detection by any station other than the intended recipient
DAn emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C07

What is meant by local control?

SelectAnswer
AAutomatically manipulating local station controls
BControlling a station through a local auxiliary link
CControlling a repeater using a portable handheld transceiver
DDirect manipulation of the transmitter by a control operator

4. - E1D05

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

SelectAnswer
AAny class with appropriate operator privileges
BAll except Technician Class
COnly Amateur Extra Class
DOnly General, Advanced or Amateur Extra Class

5. - E1E01

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

SelectAnswer
A5
B3
C2
D4

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

SelectAnswer
AAPRS
BBandwidth compressed LORAN
CRadar
DDoppler shift of beacon signals

8. - E2B12

How are analog SSTV images typically transmitted on the HF bands?

SelectAnswer
AVideo is converted to equivalent ASCII representation
BVarying tone frequencies representing the video are transmitted using PSK
CVarying tone frequencies representing the video are transmitted using single sideband
DVideo is converted to equivalent Baudot representation

9. - E2C05

What is the function of a DX QSL Manager?

SelectAnswer
ATo relay calls to and from a DX station
BTo allocate frequencies for DXpeditions
CTo handle the receiving and sending of confirmation cards for a DX station
DTo run a net to allow many stations to contact a rare DX station

10. - E2D08

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

SelectAnswer
ADisconnect
BAcknowledgement
CConnect
DUnnumbered Information

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

SelectAnswer
AALE can use any type of control
BAutomatic
CLocal
DRemote

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

SelectAnswer
AElectric and magnetic fields become aligned as they travel
BChanging electric and magnetic fields propagate the energy
CThe energy propagates through a medium with a high refractive index
DThe waves are reflected by the ionosphere and return to their source

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A7500 miles
B2500 miles
C1000 miles
D5000 miles

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

SelectAnswer
APolar paths
BSporadic-E
CNVIS
DTransequatorial propagation

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ABit error rate tester
BNetwork analyzer
CModulation monitor
DLogic analyzer

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

SelectAnswer
AIt can display results directly in Smith chart format
BIt provides an excellent match under all conditions
CIt is very precise in obtaining a signal null
DIt is relatively immune to drift in the signal generator source

17. - E4C04

How is the noise figure of a receiver defined?

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

18. - E4D03

How can intermodulation interference between two repeaters occur?

SelectAnswer
AWhen the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
BWhen the signals from the transmitters are reflected out of phase from airplanes passing overhead
CWhen the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
DWhen the signals from the transmitters are reflected in phase from airplanes passing overhead

19. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

SelectAnswer
ASignals which have a sharply peaked frequency distribution
BSignals which are constant at all IF levels
CSignals which appear across a wide bandwidth
DSignals which appear at one IF but not another

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
A23.5 kHz
B7.12 MHz
C23.5 MHz
D7.12 kHz

21. - E5B12

What is admittance?

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

22. - E5C02

How are impedances described in polar coordinates?

SelectAnswer
ABy phase angle and amplitude
BBy Y and G values
CBy real and imaginary parts
DBy X and R values

23. - E5D14

What is reactive power?

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

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

SelectAnswer
AN-type
BInsulated gate
CP-type
DBipolar

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

SelectAnswer
AIt has the high input impedance of CMOS and the low output impedance of bipolar transistors
BAll of these choices are correct
CIt is totally immune to electrostatic damage
DIts simplicity results in much less expensive devices than standard CMOS

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

SelectAnswer
AElectrolytic capacitors
BFerrite beads
CSteel-core toroids
DButterworth filters

28. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

SelectAnswer
A-20 dBm
B-10 dB
C44 dBm
D2 dB

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 for generating RTTY signals by means of a rotating light source
CA device which measures the strength of a beam of light using analog to digital conversion
DA digital encryption device often used to encrypt spacecraft control signals

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

SelectAnswer
AA flip-flop
BAn XOR gate
CA multiplexer
DAn OR gate

31. - E7B13

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

SelectAnswer
ACollector load
BFixed bias
CVoltage regulation
DEmitter load

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

SelectAnswer
AA Chebyshev filter
BA Butterworth filter
CA passive op-amp filter
DAn active LC filter

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

SelectAnswer
AInput voltage multiplied by input current
BInput voltage divided by output current
CVoltage difference from input to output multiplied by output current
DOutput voltage multiplied by output current

34. - E7E10

How does a diode detector function?

SelectAnswer
ABy rectification and filtering of RF signals
BBy sensing the change of reactance in the diode with respect to frequency
CBy mixing signals with noise in the transition region of the diode
DBy breakdown of the Zener voltage

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

SelectAnswer
AIt removes high-frequency signal components which would otherwise be reproduced as lower frequency components
BIt removes low frequency signal components to eliminate the need for DC restoration
CIt notches out the sampling frequency to avoid sampling errors
DIt peaks the response of the decimator, improving bandwidth

36. - E7G02

What is the effect of ringing in a filter?

SelectAnswer
AUndesired oscillations added to the desired signal
BPartial cancellation of the signal over a range of frequencies
CAn echo caused by a long time delay
DA reduction in high frequency response

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

SelectAnswer
ATaft, Pierce and negative feedback
BColpitts, Hartley and Pierce
CTaft, Hartley and Pierce
DPierce, Fenner and Beane

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

SelectAnswer
ADigital signals always occupy a narrower bandwidth
BLess complex circuitry is required for digital signal generation and detection
CAll of these choices are correct
DDigital signals can be regenerated multiple times without error

39. - E8B09

What is meant by deviation ratio?

SelectAnswer
AThe ratio of the highest audio modulating frequency to the average audio modulating frequency
BThe ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
CThe ratio of the audio modulating frequency to the center carrier frequency
DThe ratio of the carrier center frequency to the audio modulating frequency

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

SelectAnswer
AIt is easier to demodulate with a conventional, non-synchronous detector
BThis results in the least possible transmitted bandwidth for the particular mode
CAll of these choices are correct
DIt improves carrier suppression

41. - E8D09

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

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

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

SelectAnswer
A78.7 watts
B1977 watts
C420 watts
D286 watts

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

SelectAnswer
AThe gain may change depending on frequency
BThe E-field and H-field patterns may reverse
CElement spacing limits could be exceeded
DFeed point impedance may become negative

44. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

SelectAnswer
AA figure-8 oriented along the axis of the array
BCardioid
CA figure-8 broadside to the axis of the array
DOmni-directional

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

SelectAnswer
AIt might radiate harmonics
BIt is too sharply directional at lower frequencies
CIt radiates the harmonics and fundamental equally well
DIt must be neutralized

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

SelectAnswer
AIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
BIt makes sure the antenna has a low-angle radiation pattern
CIt allows single-band antennas to operate on other bands
DIt ensures that each driven element operates in concert with the others to create the desired antenna pattern

47. - E9F11

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

SelectAnswer
AA capacitive reactance
BAn inductive reactance
CThe same as the characteristic impedance of the line
DThe same as the input impedance of the final generator stage

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

SelectAnswer
AStanding wave ratio circles
BRadiation-pattern circles
CAntenna-length circles
DCoaxial-length circles

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

SelectAnswer
AOne or more turns of wire wound in the shape of a large open coil
BA large circularly polarized antenna
CA small coil of wire tightly wound around a toroidal ferrite core
DA vertical antenna coupled to a feed line through an inductive loop of wire

50. - E0A01

What is the primary function of an external earth connection or ground rod?

SelectAnswer
AReduce RFI to telephones and home entertainment systems
BReduce received noise
CReduce RF current flow between pieces of equipment
DLightning protection

Figure E7-2