Anonymous User

Hamboozler

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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

SelectAnswer
AEnsure signals from your station are less than the uncontrolled Maximum Permitted Emission (MPE) limits
BEnsure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits
CEnsure signals from your station are less than the controlled Maximum Permitted Exposure (MPE) limits
DEnsure signals from your station are less than the uncontrolled Maximum Permitted Exposure (MPE) limits

2. - E1A05

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

SelectAnswer
A50 watts PEP effective radiated power relative to a dipole
B50 watts PEP effective radiated power relative to an isotropic radiator
C100 watts PEP effective radiated power relative to an isotropic radiator
D100 watts PEP effective radiated power relative to the gain of a half-wave dipole

3. - E1B02

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

SelectAnswer
A20 kHz
B3 kHz
C15 kHz
D10 kHz

4. - E1C01

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

SelectAnswer
A170 Hz
B60 Hz
C1.5 kHz
D2.8 kHz

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

SelectAnswer
AA space station, beacon station, or telecommand station
BAll these choices are correct
CA local repeater or linked repeater station
DA message forwarding station or automatically controlled digital station

6. - E1E01

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

SelectAnswer
APreparing, processing, administering, and coordinating an examination for an amateur radio operator license
BNo expenses are authorized for reimbursement
CProviding amateur operator license examination preparation training materials
DTeaching an amateur operator license examination preparation course

7. - E1F08

Which of the following types of amateur station communications are prohibited?

SelectAnswer
ACommunications that have political content, except as allowed by the Fairness Doctrine
BCommunications in a language other than English
CCommunications that have religious content
DCommunications transmitted for hire or material compensation, except as otherwise provided in the rules

8. - E2A13

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

SelectAnswer
ANode hopping
BStore-and-forward
CMulti-satellite relaying
DDigipeating

9. - E2B04

How is color information sent in analog SSTV?

SelectAnswer
AColor is amplitude modulated on the frequency modulated intensity signal
BColor is sent in a color burst at the end of each line
CColor lines are sent sequentially
DColor information is sent on a 2.8 kHz subcarrier

10. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

SelectAnswer
ASend the call sign of the DX station three times, the words this is,then your call sign three times
BSend your full call sign and grid square
CSend your full call sign once or twice
DSend only the last two letters of your call sign until you make contact

11. - E2D05

What is one advantage of the JT65 mode?

SelectAnswer
AEasily copied by ear if necessary
BThe ability to decode signals which have a very low signal-to-noise ratio
CPermits fast-scan TV transmissions over narrow bandwidth
DUses only a 65 Hz bandwidth

12. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

SelectAnswer
APSK31
BPACTOR
CMT63
DRTTY

13. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

SelectAnswer
ABodies of water
BMountain ranges
CUrban areas
DForests

14. - E3B02

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

SelectAnswer
A1000 miles
B5000 miles
C2500 miles
D7500 miles

15. - E3C01

What does the radio communication term "ray tracing" describe?

SelectAnswer
AEvaluating high voltage sources for x-rays
BThe process in which an electronic display presents a pattern
CDetermining the radiation pattern from an array of antennas
DModeling a radio wave's path through the ionosphere

16. - E4A08

Which of the following measures SWR?

SelectAnswer
AAn ohmmeter
BA spectrum analyzer
CA Q meter
DAn antenna analyzer

17. - E4B03

Which S parameter is equivalent to forward gain?

SelectAnswer
AS21
BS12
CS22
DS11

18. - E4C12

Which of the following has the largest effect on an SDR receiver's dynamic range?

SelectAnswer
ARAM speed used for data storage
BCPU register width in bits
CAnalog-to-digital converter sample width in bits
DAnti-aliasing input filter bandwidth

19. - 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
A146.34 MHz and 146.61 MHz
B146.10 MHz and 147.30 MHz
C146.88 MHz and 146.34 MHz
D173.35 MHz and 139.40 MHz

20. - E4E06

What is one type of electrical interference that might be caused by a nearby personal computer?

SelectAnswer
AA whining type noise that continually pulses off and on
BThe appearance of unstable modulated or unmodulated signals at specific frequencies
CA loud AC hum in the audio output of your station receiver
DA clicking noise at intervals of a few seconds

21. - E5A05

What is the result of increasing the Q of an impedance-matching circuit?

SelectAnswer
AMatching bandwidth is increased
BMatching bandwidth is decreased
CIt has no effect on impedance matching
DMatching range is increased

22. - E5B06

What is susceptance?

SelectAnswer
AThe magnetic impedance of a circuit
BA measure of the efficiency of a transformer
CThe ratio of magnetic field to electric field
DThe imaginary part of admittance

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

SelectAnswer
AThe X axis represents the phase angle and the Y axis represents the magnitude
BThe X axis represents the reactive component and the Y axis represents the resistive component
CThe X axis represents the resistive component and the Y axis represents the reactive component
DThe X axis represents the magnitude and the Y axis represents the phase angle

24. - E5D03

What is microstrip?

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

25. - 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
BAlpha cutoff frequency
CBeta cutoff frequency
DCorner frequency

26. - E6B08

Which of the following is a Schottky barrier diode?

SelectAnswer
AThermionic emission diode
BPIN junction
CElectrolytic rectifier
DMetal-semiconductor junction

27. - E6C03

What is tri-state logic?

SelectAnswer
ALow-power logic devices designed to operate at 3 volts
BLogic devices with 0, 1, and high-impedance output states
CProprietary logic devices manufactured by Tri-State Devices
DLogic devices that utilize ternary math

28. - E6D12

What is inductor saturation?

SelectAnswer
AThe inductor's voltage rating is exceeded causing a flashover
BAdjacent inductors become over-coupled
CThe inductor windings are over-coupled
DThe ability of the inductor's core to store magnetic energy has been exceeded

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

SelectAnswer
AExcessive lead length
BUnsuitable for combining analog and digital signals
CEpoxy coating is conductive above 300 MHz
DToo many pins

30. - E6F06

Which of these materials is most commonly used to create photoconductive devices?

SelectAnswer
AA heavy metal
BA liquid semiconductor
CAn ordinary metal
DA crystalline semiconductor

31. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

SelectAnswer
A2
B4
C8
D1

32. - E7B01

For what portion of the signal cycle does each active element in a push-pull Class AB amplifier conduct?

SelectAnswer
AExactly 180 degrees
BLess than 180 degrees
CMore than 180 degrees but less than 360 degrees
DThe entire cycle

33. - E7C06

What are the distinguishing features of an elliptical filter?

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

34. - E7D13

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

SelectAnswer
AVoltage difference from input to output multiplied by output current
BInput voltage divided by output current
CInput voltage multiplied by input current
DOutput voltage multiplied by output current

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

SelectAnswer
AA circuit for detecting FM signals
BAn FM generator circuit
CA circuit for filtering two closely adjacent signals
DAn automatic band-switching circuit

36. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

SelectAnswer
A6 bits
B4 bits
C10 bits
D8 bits

37. - E7G02

What is ringing in a filter?

SelectAnswer
AA reduction in high frequency response
BAn echo caused by a long time delay
CPartial cancellation of the signal over a range of frequencies
DUndesired oscillations added to the desired signal

38. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

SelectAnswer
AWirewound resistors
BNP0 capacitors
CNon-inductive resistors
DToroidal inductors

39. - E8A10

What is the purpose of a low-pass filter used in conjunction with a digital-to-analog converter?

SelectAnswer
ALower the input bandwidth to increase the effective resolution
BRemove harmonics from the output caused by the discrete analog levels generated
CAll these choices are correct
DImprove accuracy by removing out-of-sequence codes from the input

40. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

SelectAnswer
A47
B0.214
C0.47
D2.14

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

SelectAnswer
AAll these choices are correct
BIF bandwidth and Q
CKeying speed and shape factor (rise and fall time)
DModulation index and output power

42. - E8D02

What spread spectrum communications technique uses a high-speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
ABinary phase-shift keying
BPhase compandored spread spectrum
CDirect sequence
DFrequency hopping

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

SelectAnswer
A159 watts
B63.2 watts
C252 watts
D632 watts

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

SelectAnswer
A75 degrees
B30 degrees
C50 degrees
D25 degrees

45. - 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
AOmni-directional
BA figure-8 oriented along the axis of the array
CCardioid
DA figure-8 broadside to the axis of the array

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

SelectAnswer
AArrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
BStack two Yagis fed in phase to form an array with the respective elements in parallel planes
CArrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
DStack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes

47. - E9E09

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

SelectAnswer
AHairpin match
BGamma match
CAll these choices are correct
DDouble-bazooka match

48. - E9F12

What impedance does a 1/4-wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AVery low impedance
BThe same as the input impedance to the generator
CThe same as the characteristic impedance of the line
DVery high impedance

49. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

SelectAnswer
AResistance and reactance
BVoltage and impedance
CResistance and voltage
DReactance and voltage

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

SelectAnswer
AA very sharp single null
BBroadband response
CA very sharp peak
DHigh radiation angle

Figure E9-1