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. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

SelectAnswer
AEach transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded.
BOnly the most powerful transmitter
COnly commercial transmitters
DEach transmitter operating with a duty cycle greater than 50 percent

2. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

SelectAnswer
AAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
BOnly a person with an FCC Marine Radio license grant
COnly a person named in an amateur station license grant
DAny person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit

3. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

SelectAnswer
AThe amateur station must cease operation on all frequencies above 30 MHz
BThe amateur station must cease operation
CThe amateur station must cease operation on all frequencies below 30 MHz
DThe amateur station must avoid transmitting during certain hours on frequencies that cause the interference

4. - E1C07

At what level below a signal's mean power level is its bandwidth determined according to FCC rules?

SelectAnswer
A23 dB
B6 dB
C3 dB
D26 dB

5. - E1D07

Which HF amateur bands have frequencies authorized for space stations?

SelectAnswer
AAll HF bands
BOnly the 40, 20, 17, 15, and 10 meter bands
COnly the 40, 30, 20, 15, 12, and 10 meter bands
DOnly the 40, 20, 17, 15, 12, and 10 meter bands

6. - E1E12

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

SelectAnswer
ASend the application form to the FCC and inform the FCC of the grade
BDestroy the application form
CMaintain the application form with the VEC's records
DReturn the application document to the examinee

7. - E1F07

When may an amateur station send a message to a business?

SelectAnswer
AWhen the control operator is employed by the FCC or another government agency
BWhen neither the amateur nor his or her employer has a pecuniary interest in the communications
CWhen transmitting international third-party communications
DWhen the total money involved does not exceed $25

8. - E2A04

What is meant by the term mode? as applied to an amateur radio satellite?

SelectAnswer
AThe satellite's uplink and downlink frequency bands
BWhether the satellite is in a polar or equatorial orbit
CWhether the satellite is in a low earth or geostationary orbit
DThe satellite's orientation with respect to the Earth

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

SelectAnswer
AUsing USB and demodulating the signal with a computer sound card
BTransmitting on channels shared with cable TV
CTransmitting on the abandoned TV channel 2
DUsing converted satellite TV dishes

10. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

SelectAnswer
A2 meters
B33 centimeters
C6 meters
D30 meters

11. - E2D08

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

SelectAnswer
AAcknowledgement
BUnnumbered Information
CConnect
DDisconnect

12. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

SelectAnswer
AHellschreiber
BRTTY
CAMTOR
DPACTOR

13. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

SelectAnswer
AWhen the MUF is above 30 MHz
BWhen the moon is at perigee
CWhen the moon is at apogee
DWhen the moon is full

14. - E3B02

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

SelectAnswer
A5000 miles
B2500 miles
C1000 miles
D7500 miles

15. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

SelectAnswer
ABy approximately 50 percent of the distance
BBy approximately four times the distance
CBy approximately 15 percent of the distance
DBy approximately twice the distance

16. - E4A08

Which of the following measures SWR?

SelectAnswer
AAn ohmmeter
BA Q meter
CAn antenna analyzer
DA spectrum analyzer

17. - E4B11

Which of the following can be measured with a vector network analyzer?

SelectAnswer
AReflection coefficient
BOutput impedance
CInput impedance
DAll these choices are correct

18. - E4C13

How does a narrow-band roofing filter affect receiver performance?

SelectAnswer
AIt improves sensitivity by reducing front end noise
BIt improves intelligibility by using low Q circuitry to reduce ringing
CIt improves dynamic range by attenuating strong signals near the receive frequency
DAll these choices are correct

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
B146.88 MHz and 146.34 MHz
C146.10 MHz and 147.30 MHz
D173.35 MHz and 139.40 MHz

20. - E4E11

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

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

21. - E5A14

What is the resonant frequency of an RLC circuit if R is 22 ohms, L is 50 microhenries and C is 40 picofarads?

SelectAnswer
A1.78 MHz
B3.56 MHz
C22.36 MHz
D44.72 MHz

22. - E5B06

What is susceptance?

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

23. - E5C06

What does the impedance 50-j25 represent?

SelectAnswer
A25 ohms resistance in series with 50 ohms inductive reactance
B50 ohms resistance in series with 25 ohms inductive reactance
C50 ohms resistance in series with 25 ohms capacitive reactance
D25 ohms resistance in series with 50 ohms capacitive reactance

24. - E5D08

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

SelectAnswer
A1600 watts
B1000 watts
C600 watts
D200 watts

25. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

SelectAnswer
ABase-to-emitter resistance of approximately 6 to 7 ohms
BBase-to-emitter voltage of approximately 0.6 to 0.7 volts
CBase-to-emitter resistance of approximately 0.6 to 0.7 ohms
DBase-to-emitter voltage of approximately 6 to 7 volts

26. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

SelectAnswer
ALonger carrier retention time
BLess forward voltage drop
CMuch higher reverse voltage breakdown
DMore constant reverse avalanche voltage

27. - E6C03

What is tri-state logic?

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

28. - E6D09

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

SelectAnswer
AButterworth filters
BElectrolytic capacitors
CFerrite beads
DSteel-core toroids

29. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

SelectAnswer
ATwo chips in each package (Dual In Package)
BLow leakage doubly insulated package
CPackage mounts in a direct inverted position
DA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)

30. - E6F04

What is the photovoltaic effect?

SelectAnswer
AThe conversion of voltage to current when exposed to light
BThe tendency of a battery to discharge when exposed to light
CThe conversion of electrical energy to mechanical energy
DThe conversion of light to electrical energy

31. - E7A03

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

SelectAnswer
AAn XOR gate
BA multiplexer
CA flip-flop
DAn OR gate

32. - E7B01

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

SelectAnswer
ALess than 180 degrees
BMore than 180 degrees but less than 360 degrees
CThe entire cycle
DExactly 180 degrees

33. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

SelectAnswer
AReactive currents are dissipated in matched resistances
BIt introduces transconductance to cancel the reactive part of impedance
CIt introduces negative resistance to cancel the resistive part of impedance
DIt cancels the reactive part of the impedance and changes the resistive part to a desired value

34. - E7D01

How does a linear electronic voltage regulator work?

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

35. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
AFor compatibility with transmitters using phase modulation
BTo remove third-order distortion products
CFor higher efficiency
DTo reduce impulse noise reception

36. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

SelectAnswer
AA Hilbert-transform filter
BAn adaptive filter
CA crystal-lattice filter
DA phase-inverting filter

37. - E7G02

What is ringing in a filter?

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

38. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

SelectAnswer
AThrough link coupling
BThrough a neutralizing capacitor
CThrough a capacitive divider
DThrough a tapped coil

39. - E8A09

How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

SelectAnswer
A256 divided by the gain of the input amplifier
B256
C8 multiplied by the gain of the input amplifier
D8

40. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

SelectAnswer
AA digital mode for narrow-band, slow-speed transmissions
BA frequency modulation technique that uses non-harmonically related frequencies
CA bandwidth compression technique using Fourier transforms
DA digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

41. - E8C10

How may data rate be increased without increasing bandwidth?

SelectAnswer
AIncreasing analog-to-digital conversion resolution
BIt is impossible
CUsing a more efficient digital code
DUsing forward error correction

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
BBaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
CBaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
DBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

SelectAnswer
A317 watts
B300 watts
C126 watts
D2000 watts

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

SelectAnswer
A28 dB
B3 dB
C15 dB
D38 dB

45. - E9C13

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with increasing height above ground?

SelectAnswer
AThe takeoff angle of the lowest elevation lobe increases
BThe takeoff angle of the lowest elevation lobe decreases
CThe horizontal beamwidth decreases
DThe horizontal beamwidth increases

46. - E9D11

Which of the following conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
ASolid wire
BStranded wire
CWide flat copper strap
DResistive wire, such as spark plug wire

47. - E9E07

What parameter describes the interactions at the load end of a mismatched transmission line?

SelectAnswer
ADielectric constant
BReflection coefficient
CVelocity factor
DCharacteristic impedance

48. - E9F09

What is the approximate physical length of a foam polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 7.2 MHz?

SelectAnswer
A6.9 meters
B10.4 meters
C5.2 meters
D8.3 meters

49. - E9G09

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

SelectAnswer
ACoaxial-length circles
BRadiation-pattern circles
CAntenna-length circles
DStanding wave ratio circles

50. - E9H06

What is the triangulation method of direction finding?

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