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US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

SelectAnswer
AE field and H field radiation intensity peaks can occur at different locations
BThe body reacts to electromagnetic radiation from both the E and H fields
CGround reflections and scattering make the field strength vary with location
DAll these choices are correct

2. - E1A03

What is the maximum legal carrier frequency on the 20 meter band for transmitting USB AFSK digital signals having a 1 kHz bandwidth?

SelectAnswer
A14.070 MHz
B14.349 MHz
C14.100 MHz
D14.149 MHz

3. - E1B07

To what type of regulations does PRB-1 apply?

SelectAnswer
AHomeowners associations
BFAA tower height limits
CState and local zoning
DUse of wireless devices in vehicles

4. - E1C10

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

5. - E1D03

What is a space telecommand station?

SelectAnswer
AAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
BAn amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites
CAn amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
DAn amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth

6. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
AFriends of the VE
BAll these choices are correct
CRelatives of the VE as listed in the FCC rules
DEmployees of the VE

7. - E1F09

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

SelectAnswer
AA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
BAll these choices are correct
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

8. - E2A09

What do the terms L band and S band specify regarding satellite communications?

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

9. - E2B05

Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?

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

10. - E2C01

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control and the remote transmitter is located in the U.S.?

SelectAnswer
ANo additional indicator is required
B/ followed by the ARRL Section of the remote station
C/ followed by the USPS two-letter abbreviation for the state in which the remote station is located
D/R# where # is the district of the remote station

11. - E2D04

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

SelectAnswer
AUltrasonics
BAPRS
CDoppler shift of beacon signals
DBandwidth compressed LORAN

12. - E2E13

Which of these digital modes has the fastest data throughput under clear communication conditions?

SelectAnswer
APSK31
B170 Hz shift, 45 baud RTTY
CAMTOR
D300 baud packet

13. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by EME?

SelectAnswer
A12,000 miles, if the moon is visible by both stations
B2000 miles, if the moon is at apogee
C500 miles, if the moon is at perigee
D5000 miles, if the moon is at perigee

14. - E3B02

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

SelectAnswer
A7500 miles
B2500 miles
C5000 miles
D1000 miles

15. - E3C11

What does VOACAP software model?

SelectAnswer
AAC voltage and impedance
BVHF radio propagation
CHF propagation
DAC current and impedance

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

SelectAnswer
ASWR and frequency
BSWR and time
CRF amplitude and frequency
DRF amplitude and time

17. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

SelectAnswer
A100 watts
B25 watts
C125 watts
D75 watts

18. - E4C03

What is the term for the suppression in an FM receiver of one signal by another stronger signal on the same frequency?

SelectAnswer
AFrequency discrimination
BCross-modulation interference
CDesensitization
DCapture effect

19. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

SelectAnswer
AQuieting
BDesensitization
CCross-modulation interference
DSquelch gain rollback

20. - E4E11

What could cause local AM broadcast band signals to combine to generate spurious signals in the MF or HF bands?

SelectAnswer
AOne or more of the broadcast stations is transmitting an over-modulated signal
BNearby corroded metal joints are mixing and re-radiating the broadcast signals
CYour station receiver IF amplifier stage is defective
DYou are receiving skywave signals from a distant station

21. - E5A01

What can cause the voltage across reactances in a series RLC circuit to be higher than the voltage applied to the entire circuit?

SelectAnswer
AResistance
BResonance
CCapacitance
DConductance

22. - E5B12

What is admittance?

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

23. - E5C12

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

SelectAnswer
APoint 7
BPoint 8
CPoint 1
DPoint 3

24. - E5D03

What is microstrip?

SelectAnswer
AShort lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
BLightweight transmission line made of common zip cord
CPrecision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
DMiniature coax used for low power applications

25. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

SelectAnswer
AExcess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
BHoles in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
COnly N-type semiconductor material can conduct current
DOnly P-type semiconductor material can conduct current

26. - E6B03

What type of bias is required for an LED to emit light?

SelectAnswer
AReverse bias
BForward bias
CZero bias
DInductive bias

27. - E6C01

What is the function of hysteresis in a comparator?

SelectAnswer
ATo allow the comparator to be used with AC input signals
BTo cause the output to change states continually
CTo increase the sensitivity
DTo prevent input noise from causing unstable output signals

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

SelectAnswer
ABrass
BPowdered iron
CFerrite
DCeramic

29. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

SelectAnswer
ASilicon
BSilicon nitride
CSilicon dioxide
DGallium nitride

30. - E6F02

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

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

31. - E7A01

Which circuit is bistable?

SelectAnswer
AA flip-flop
BAn AND gate
CA bipolar amplifier
DAn OR gate

32. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

SelectAnswer
AReduced intermodulation products
BSignal distortion and excessive bandwidth
CSignal inversion
DIncreased overall intelligibility

33. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with minimal stop band ripple
BExtremely flat response over its pass band with gradually rounded stop band corners
CExtremely sharp cutoff with one or more notches in the stop band
DGradual passband rolloff with extreme stop band ripple

34. - E7D13

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

SelectAnswer
AOutput voltage multiplied by output current
BInput voltage divided by output current
CInput voltage multiplied by input current
DVoltage difference from input to output multiplied by output current

35. - E7E01

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

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

36. - E7F09

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

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

37. - E7G06

What is the gain-bandwidth of an operational amplifier?

SelectAnswer
AThe gain of the amplifier at a filter's cutoff frequency
BThe maximum frequency for a filter circuit using that type of amplifier
CThe frequency at which the amplifier's offset voltage is zero
DThe frequency at which the open-loop gain of the amplifier equals one

38. - E7H15

Which of these functions can be performed by a phase-locked loop?

SelectAnswer
AFrequency synthesis, FM demodulation
BPhotovoltaic conversion, optical coupling
CWide-band AF and RF power amplification
DComparison of two digital input signals, digital pulse counter

39. - E8A11

Which of the following is a measure of the quality of an analog-to-digital converter?

SelectAnswer
ATotal harmonic distortion
BReciprocal mixing
CPeak envelope power
DPower factor

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

SelectAnswer
A60
B0.167
C0.6
D1.67

41. - E8C08

How does ARQ accomplish error correction?

SelectAnswer
ASpecial polynomial codes provide automatic correction
BIf errors are detected, a retransmission is requested
CSpecial binary codes provide automatic correction
DIf errors are detected, redundant data is substituted

42. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

SelectAnswer
AThe generation of key clicks
BLimits data speed
CThe generation of RF harmonics
DMore difficult to copy

43. - E9A03

What is 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 value of a resistance that would dissipate the same amount of power as that radiated from an antenna
CThe specific impedance of the antenna
DThe combined losses of the antenna elements and feed line

44. - E9B11

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

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

45. - E9C12

Which of the following describes an Extended Double Zepp antenna?

SelectAnswer
AA wideband vertical antenna constructed from precisely tapered aluminum tubing
BA portable antenna erected using two push support poles
CAn end-fed folded dipole antenna
DA center-fed 1.25-wavelength antenna (two 5/8-wave elements in phase)

46. - E9D06

What happens to the SWR bandwidth when one or more loading coils are used to resonate an electrically short antenna?

SelectAnswer
AIt is increased
BIt is unchanged if the loading coil is located at a voltage maximum point
CIt is unchanged if the loading coil is located at the feed point
DIt is decreased

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

SelectAnswer
AAll these choices are correct
BGamma match
CDouble-bazooka match
DHairpin match

48. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

SelectAnswer
ASmaller reflection coefficient
BHigher SWR
CLower loss
DLower velocity factor

49. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
AFrequency
BSWR
CPoints with constant resistance
DPoints with constant reactance

50. - E9H08

What is the function of a sense antenna?

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

Figure E5-1