Anonymous User

Hamboozler

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

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

1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

SelectAnswer
AYes, because the displayed frequency is within the 75 meter phone band segment
BYes, because the DX station initiated the contact
CNo, the sideband will extend beyond the edge of the phone band segment
DNo, U.S. stations are not permitted to use phone emissions below 3.610 MHz

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

SelectAnswer
A0.5
B2.0
C1.0
D3.0

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

SelectAnswer
AOnly earth stations, repeater stations or model craft
BOnly beacon, repeater or space stations
COnly auxiliary, repeater or space stations
DOnly auxiliary, beacon or space stations

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

SelectAnswer
A6 meters, 2 meters, and 1.25 meters
B6 meters and 2 meters
C2 meters and 1.25 meters
D2 meters

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

SelectAnswer
AAll of these choices are correct
BA sentence of up to one year in prison
CA fine of up to $1000 per occurrence
DRevocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

SelectAnswer
ATo provide temporary operation while awaiting normal licensing
BTo provide for experimental amateur communications
CTo provide additional spectrum for personal use
DTo allow regular operation on Land Mobile channels

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

SelectAnswer
AFrom south to north
BFrom west to east
CFrom east to west
DFrom north to south

8. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

SelectAnswer
A2 MHz
B3 kHz
C600 Hz
D6 MHz

9. - E2C03

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

SelectAnswer
A6 m
B30 m
C33 cm
D2 m

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

SelectAnswer
AHellschreiber
BWSPR
CAPRS
DFSK441

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

SelectAnswer
AFinal Error Correction
BFirst Error Correction
CForward Error Correction
DFatal Error Correction

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

SelectAnswer
A100 miles to 300 miles
B2500 miles
C10 miles to 50 miles
D1200 miles

13. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
ASignals reflected back toward the transmitting station
BPropagation away from the great circle bearing between stations
CPropagation across the geomagnetic equator
DSuccessive ionospheric reflections without an intermediate reflection from the ground

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

SelectAnswer
ADownward bending due to aurora refraction
BE-region skip
CD-region skip
DDownward bending due to density variations in the atmosphere

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

SelectAnswer
AOne-tenth the sample rate
BOne-half the sample rate
CThe same as the sample rate
DIt depends on how the data is stored internally

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

SelectAnswer
A50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
BShort circuit, open circuit, and 50 ohms
CShort circuit, open circuit, and resonant circuit
D50 ohms, 75 ohms, and 90 ohms

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

SelectAnswer
AOverload
BExcess output level
CDistortion
DLoss of sensitivity

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
A173.35 MHz and 139.40 MHz
B146.10 MHz and 147.30 MHz
C146.88 MHz and 146.34 MHz
D146.34 MHz and 146.61 MHz

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

SelectAnswer
ABroadband white noise
BAll of these choices are correct
CPower line noise
DIgnition noise

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

SelectAnswer
AApproximately equal to capacitive reactance
BApproximately equal to circuit resistance
CApproximately equal to inductive reactance
DHigh, as compared to the circuit resistance

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

SelectAnswer
A76 degrees with the voltage lagging the current
B76 degrees with the voltage leading the current
C14 degrees with the voltage lagging the current
D14 degrees with the voltage leading the current

22. - E5C07

What is a vector?

SelectAnswer
AThe inverse of the tangent function
BThe inverse of the sine function
CThe value of a quantity that changes over time
DA quantity with both magnitude and an angular component

23. - E5D04

Why are short connections necessary at microwave frequencies?

SelectAnswer
ATo reduce noise figure
BTo increase neutralizing resistance
CBecause of ground reflections
DTo reduce phase shift along the connection

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

SelectAnswer
AInsulator impurity
BN-type impurity
CDonor impurity
DAcceptor impurity

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

SelectAnswer
ATunnel diode
BVaractor diode
CSilicon-controlled rectifier
DZener diode

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

SelectAnswer
AAll of these choices are correct
BA PGA contains its own internal power supply
CMany similar gates are less expensive than a mixture of gate types
DComplex logic functions can be created in a single integrated circuit

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

SelectAnswer
ASnubber capacitor
BTrimmer capacitor
CFeedback capacitor
DClipper capacitor

28. - E6E03

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

SelectAnswer
AGallium nitride
BSilicon
CSilicon nitride
DSilicon dioxide

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

SelectAnswer
AHoles
BProtons
CPhotons
DElectrons

30. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
ANegative logic
BPositive Logic
CReverse Logic
DAssertive Logic

31. - E7B02

What is a Class D amplifier?

SelectAnswer
AA type of amplifier that uses switching technology to achieve high efficiency
BA low power amplifier that uses a differential amplifier for improved linearity
CAn amplifier that uses drift-mode FETs for high efficiency
DA frequency doubling amplifier

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

SelectAnswer
AIt uses a diode bridge rectifier for increased output
BThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
CThe inverter design does not require any output filtering
DIt uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

SelectAnswer
A1.414 and 0.707 times the input frequency
BThe sum, difference and square root of the input frequencies
CTwo and four times the original frequency
DThe two input frequencies along with their sum and difference frequencies

35. - 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 phase-inverting filter
DA crystal-lattice filter

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

SelectAnswer
A-0.23 volts
B0.23 volts
C-2.3 volts
D2.3 volts

37. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
BAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
CAn electronic circuit consisting of a precision push-pull amplifier with a differential input
DAn electronic circuit also known as a monostable multivibrator

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

SelectAnswer
AA sawtooth wave
BA sine wave
CA square wave
DA cosine wave

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

SelectAnswer
AFM compressibility
BModulation index
CPercentage of modulation
DQuieting index

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A9.6 kHz
B5.76 kHz
C15.36 kHz
D4.8 kHz

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

SelectAnswer
ABaud rate
BRepeat Request Rate (RRR)
CSignal to noise ratio
DIntermodulation Distortion (IMD)

42. - E9A05

What is included in the total resistance of an antenna system?

SelectAnswer
ATransmission-line resistance plus radiation resistance
BRadiation resistance plus transmission resistance
CRadiation resistance plus space impedance
DRadiation resistance plus ohmic resistance

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
BThe computed feed point impedance may be incorrect
CGround conductivity will not be accurately modeled
DThe resulting design will favor radiation of harmonic energy

44. - E9C09

What is a G5RV antenna?

SelectAnswer
AA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
BA phased array antenna consisting of multiple loops
CA multi-band trap antenna
DA wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun

45. - E9D11

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

SelectAnswer
AA cable with six or seven 18 gauge conductors in parallel
BA resistive wire, such as spark plug wire
CA single 12 gauge or 10 gauge stainless steel wire
DA wide flat copper strap

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

SelectAnswer
AThe driven element radiation resistance must be higher than the characteristic impedance of the transmission line
BThe driven element reactance must be inductive
CThe driven element reactance must be capacitive
DThe driven element resonance must be lower than the operating frequency

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

SelectAnswer
AThe surge impedance is higher in a parallel feed line
BElectrical signals move more slowly in a coaxial cable than in air
CSkin effect is less pronounced in the coaxial cable
DThe characteristic impedance is higher in a parallel feed line

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
BCoaxial-length circles
CAntenna-length circles
DRadiation-pattern 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 vertical antenna coupled to a feed line through an inductive loop of wire
CA large circularly polarized antenna
DA small coil of wire tightly wound around a toroidal ferrite core

50. - E0A08

What does SAR measure?

SelectAnswer
AThe rate of RF energy reflected from stationary terrain
BSynthetic Aperture Ratio of the human body
CThe rate at which RF energy is absorbed by the body
DSignal Amplification Rating

Figure E7-4