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

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1. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

SelectAnswer
APolytetrafluoroethylene
BPolyethylene
CPolymorphic silicon
DPolychlorinated biphenyls

2. - 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
B50 watts PEP effective radiated power relative to a dipole
C50 watts PEP effective radiated power relative to an isotropic radiator
D100 watts PEP effective radiated power relative to an isotropic radiator

3. - E1B07

To what type of regulations does PRB-1 apply?

SelectAnswer
AState and local zoning
BUse of wireless devices in vehicles
CFAA tower height limits
DHomeowners associations

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

SelectAnswer
AOperators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
BOperators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station
CA special endorsement must be requested from the FCC
DAn environmental impact statement must be filed with the Department of the Interior

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

SelectAnswer
A70 cm and 33 cm
B70 cm and 13 cm
C33 cm and 13 cm
D70 cm only

6. - E1E12

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

SelectAnswer
ADestroy the application form
BMaintain the application form with the VEC's records
CSend the application form to the FCC and inform the FCC of the grade
DReturn the application document to the examinee

7. - 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

8. - E2A01

What is the direction of an ascending pass for an amateur satellite?

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

9. - E2B04

How is color information sent in analog SSTV?

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

10. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

SelectAnswer
ASpecial event contacts between stations in the U.S.
BRepeater contacts between U.S. club members
CContacts using tactical call signs
DContacts between a U.S. station and a non-U.S. station

11. - E2D11

Which of the following data are used by the APRS network to communicate station location?

SelectAnswer
APolar coordinates
BTime and frequency
CLatitude and longitude
DRadio direction finding spectrum analysis

12. - E2E13

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

SelectAnswer
A170 Hz shift, 45 baud RTTY
B300 baud packet
CPSK31
DAMTOR

13. - E3A12

What is the cause of auroral activity?

SelectAnswer
AMeteor showers concentrated in the extreme northern and southern latitudes
BAn extreme low-pressure area in the polar regions
CThe interaction in the F2 layer between the solar wind and the Van Allen belt
DThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field

14. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between points at the same latitude
BPropagation between a point on the equator and its antipodal point
CPropagation between points located on the magnetic equator
DPropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator

15. - E3C11

What does VOACAP software model?

SelectAnswer
AVHF radio propagation
BAC current and impedance
CAC voltage and impedance
DHF propagation

16. - E4A09

Which of the following is good practice when using an oscilloscope probe?

SelectAnswer
ANever use a DC-coupled probe to measure an AC circuit
BAll these choices are correct
CKeep the signal ground connection of the probe as short as possible
DNever use a high-impedance probe to measure a low-impedance circuit

17. - E4B03

Which S parameter is equivalent to forward gain?

SelectAnswer
AS21
BS11
CS12
DS22

18. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

SelectAnswer
A-174 dBm
B-148 dBm
C-155 dBm
D-164 dBm

19. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

SelectAnswer
AA pair of 1 mW input signals will produce a third-order intermodulation product that is 40 dB stronger than the input signal
BA pair of 40 dBm input signals will theoretically generate a third-order intermodulation product that has the same output amplitude as either of the input signals
CSignals less than 40 dBm will not generate audible third-order intermodulation products
DThe receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products

20. - E4E08

What current flows equally on all conductors of an unshielded multi-conductor cable?

SelectAnswer
AReactive current only
BReturn current
CCommon-mode current
DDifferential-mode current

21. - E5A12

What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

SelectAnswer
A31.4 kHz
B436.6 kHz
C15.7 kHz
D218.3 kHz

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

SelectAnswer
AVoltage and current are in phase
BVoltage and current are 180 degrees out of phase
CCurrent leads voltage by 90 degrees
DVoltage leads current by 90 degrees

23. - E5C11

Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

SelectAnswer
APoint 3
BPoint 8
CPoint 7
DPoint 1

24. - E5D05

What is the power factor of an RL circuit having a 30-degree phase angle between the voltage and the current?

SelectAnswer
A1.73
B0.866
C0.577
D0.5

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 cutoff frequency
BBeta cutoff frequency
CCorner frequency
DAlpha rejection frequency

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
ALess forward voltage drop
BMuch higher reverse voltage breakdown
CLonger carrier retention time
DMore constant reverse avalanche voltage

27. - E6C10

In Figure E6-3, what is the schematic symbol for a NOR gate?

SelectAnswer
A4
B3
C1
D2

28. - E6D11

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

SelectAnswer
APowdered iron
BCeramic
CBrass
DFerrite

29. - E6E11

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

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

30. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

SelectAnswer
ACadmium Sulfide
BSilicon
CCopper oxide
DSelenium

31. - E7A11

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

SelectAnswer
APositive Logic
BReverse Logic
CAssertive Logic
DNegative logic

32. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

SelectAnswer
AAll these choices are correct
BSelect transistors with high beta
CUse a resistor in series with the emitter
DNeutralization

33. - E7C11

Which of the following describes a receiving filter's ability to reject signals occupying an adjacent channel?

SelectAnswer
AShape factor
BNoise factor
CPassband ripple
DPhase response

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. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy using a loop modulator followed by a mixer
BBy using a reactance modulator followed by a mixer
CBy using a balanced modulator followed by a filter
DBy driving a product detector with a DSB signal

36. - E7F12

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

SelectAnswer
AAll these choices are correct
BFIR filters can respond faster to impulses
CFIR filters can delay all frequency components of the signal by the same amount
DFIR filters are easier to implement for a given set of passband rolloff requirements

37. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A28
B0.07
C14
D7

38. - E7H14

What is a phase-locked loop circuit?

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

39. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

SelectAnswer
AThe degree of carrier suppression
BAmplifier gain
CThe frequency of the modulating signal
DSpeech characteristics

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
B0.6
C0.167
D1.67

41. - E8C10

How may data rate be increased without increasing bandwidth?

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

42. - E8D06

What is the advantage of including parity bits in ASCII characters?

SelectAnswer
AFaster transmission rate
BThe signal can overpower interfering signals
CForeign language characters can be sent
DSome types of errors can be detected

43. - E9A08

What is antenna bandwidth?

SelectAnswer
AThe angle formed between two imaginary lines drawn through the element ends
BThe angle between the half-power radiation points
CAntenna length divided by the number of elements
DThe frequency range over which an antenna satisfies a performance requirement

44. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

SelectAnswer
A45 degrees
B7.5 degrees
C75 degrees
D25 degrees

45. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?

SelectAnswer
AThe low-angle radiation decreases
BAdditional higher vertical angle lobes will appear
CFewer vertical angle lobes will be present
DThe low-angle radiation increases

46. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

SelectAnswer
ATo minimize the Q
BTo lower the radiation angle
CTo swamp out harmonics
DTo minimize losses

47. - E9E07

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

SelectAnswer
AReflection coefficient
BCharacteristic impedance
CDielectric constant
DVelocity factor

48. - 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
BThe characteristic impedance is higher in a parallel feed line
CElectrical signals move more slowly in a coaxial cable than in air
DSkin effect is less pronounced in the coaxial cable

49. - E9G01

Which of the following can be calculated using a Smith chart?

SelectAnswer
ARadiation resistance
BImpedance along transmission lines
CRadio propagation
DAntenna radiation pattern

50. - E9H07

Why is RF attenuation used when direction-finding?

SelectAnswer
ATo compensate for isotropic directivity and the antenna effect of feed lines
BTo increase receiver sensitivity
CTo narrow the receiver bandwidth
DTo prevent receiver overload which reduces pattern nulls

Figure E5-1

Figure E6-3

Figure E7-3

Figure E9-2