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. - E0A03

Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

SelectAnswer
A300 to 3000 MHz
B30 to 300 MHz
C300 kHz to 3 MHz
D3 to 30 MHz

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. - E1B12

What must the control operator of a repeater operating in the 70 cm band do if a radiolocation system experiences interference from that repeater?

SelectAnswer
AFile an FAA NOTAM (Notice to Airmen) with the repeater system's ERP, call sign, and six-character grid locator
BReduce the repeater antenna HAAT (Height Above Average Terrain)
CAll these choices are correct
DCease operation or make changes to the repeater to mitigate the interference

4. - E1C06

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

SelectAnswer
AThe U.S. embassy must approve of your operation
BYou must bring a copy of FCC Public Notice DA 16-1048
CYou must append "/CEPT" to your call sign
DYou must identify in the official language of the country in which you are operating

5. - E1D01

What is the definition of telemetry?

SelectAnswer
ATwo-way transmissions in excess of 1000 feet
BTwo-way transmissions of data
COne-way transmission that initiates, modifies, or terminates the functions of a device at a distance
DOne-way transmission of measurements at a distance from the measuring instrument

6. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

SelectAnswer
AEach administering VE
BThe FCC
CThe VE session manager
DThe VEC coordinating the session

7. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

SelectAnswer
A420 MHz - 430 MHz
B53 MHz - 54 MHz
C222 MHz - 223 MHz
D440 MHz - 450 MHz

8. - E2A12

What is the purpose of digital store-and-forward functions on an amateur radio satellite?

SelectAnswer
ATo upload operational software for the transponder
BTo relay messages between satellites
CTo delay download of telemetry between satellites
DTo store digital messages in the satellite for later download by other stations

9. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

SelectAnswer
ANo other hardware is needed
BA special IF converter
CA special front end limiter
DA special notch filter to remove synchronization pulses

10. - E2C09

What type of equipment is commonly used to implement an amateur radio mesh network?

SelectAnswer
AAn optical cable connection between the USB ports of 2 separate computers
BA wireless router running custom firmware
CA 2 meter VHF transceiver with a 1200 baud modem
DA 440 MHz transceiver with a 9600 baud modem

11. - E2D07

What digital protocol is used by APRS?

SelectAnswer
AAX.25
BPACTOR
CAMTOR
D802.11

12. - E2E08

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

SelectAnswer
ARTTY
BHellschreiber
CAMTOR
DPACTOR

13. - E3A02

What characterizes libration fading of an EME signal?

SelectAnswer
AA gradual loss of signal as the sun rises
BA slow change in the pitch of the CW signal
CThe returning echo is several hertz lower in frequency than the transmitted signal
DA fluttery irregular fading

14. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

SelectAnswer
A20 meters
B10 meters
C80 meters
D6 meters

15. - E3C12

How does the maximum range of ground-wave propagation change when the signal frequency is increased?

SelectAnswer
AIt decreases
BIt increases
CIt stays the same
DIt peaks at roughly 14 MHz

16. - E4A11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

SelectAnswer
ALoosely couple the antenna and a dummy load to the analyzer
BLoosely couple the analyzer near the antenna base
CConnect the analyzer via a high-impedance transformer to the antenna
DConnect the antenna feed line directly to the analyzer's connector

17. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

SelectAnswer
AThere is more power going into the antenna
BThere is possibly a short to ground in the feed line
CThere is an impedance mismatch between the antenna and feed line
DThe transmitter is not properly neutralized

18. - E4C15

What is reciprocal mixing?

SelectAnswer
AIn-phase signals cancelling in a mixer resulting in loss of receiver sensitivity
BLocal oscillator phase noise mixing with adjacent strong signals to create interference to desired signals
CTwo digital signals combining from alternate time slots
DTwo out-of-band signals mixing to generate an in-band spurious signal

19. - E4D07

Which of the following reduces the likelihood of receiver desensitization?

SelectAnswer
AIncrease the receiver front end gain
BDecrease the RF bandwidth of the receiver
CSwitch from fast AGC to slow AGC
DRaise the receiver IF frequency

20. - E4E07

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
ALow inductance ground connections at both ends of the shield
BCommon-mode currents on the shield and conductors
CTying all ground connections to a common point resulting in differential-mode currents in the shield
DUse of braided shielding material

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. - E5B03

How is impedance in polar form converted to an equivalent admittance?

SelectAnswer
ATake the reciprocal of the angle and change the sign of the magnitude
BSquare the magnitude and subtract 90 degrees from the angle
CTake the reciprocal of the magnitude and change the sign of the angle
DTake the square root of the magnitude and add 180 degrees to the angle

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 1
BPoint 8
CPoint 3
DPoint 7

24. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

SelectAnswer
AIt is dissipated as heat in the circuit
BIt is dissipated in the formation of inductive and capacitive fields
CIt is dissipated as kinetic energy in the circuit
DIt is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated

25. - E6A04

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

SelectAnswer
ADonor impurity
BInsulator impurity
CN-type impurity
DAcceptor impurity

26. - E6B04

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

SelectAnswer
ATunnel diode
BZener diode
CVaractor diode
DSilicon-controlled rectifier

27. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AA type of transistor whose gain can be changed by digital logic circuits
BProgrammable equipment used for testing digital logic integrated circuits
CA programmable collection of logic gates and circuits in a single integrated circuit
DA logic circuit that can be modified during use

28. - E6D03

Which of the following is an aspect of the piezoelectric effect?

SelectAnswer
AGeneration of electrical energy in the presence of light
BIncreased conductivity in the presence of light
CMechanical deformation of material by the application of a voltage
DMechanical deformation of material by the application of a magnetic field

29. - E6E10

What advantage does surface-mount technology offer at RF compared to using through-hole components?

SelectAnswer
AShorter circuit-board traces
BComponents have less parasitic inductance and capacitance
CAll these choices are correct
DSmaller circuit area

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

SelectAnswer
A0.1 V
B0.5 V
C12 V
D1.5 V

31. - E7A01

Which circuit is bistable?

SelectAnswer
AAn AND gate
BA bipolar amplifier
CAn OR gate
DA flip-flop

32. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

SelectAnswer
AAt a point where the load line intersects the zero bias current curve
BAt a point where the bias resistor equals the load resistor
CWhere the load line intersects the voltage axis
DApproximately halfway between saturation and cutoff

33. - E7C11

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

SelectAnswer
ANoise factor
BPhase response
CShape factor
DPassband ripple

34. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-2?

SelectAnswer
AIt is a brute force filter for the output
BTo self-resonate at the hum frequency
CTo provide fixed DC bias for Q1
DIt bypasses rectifier output ripple around D1

35. - E7E01

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

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

36. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

SelectAnswer
AA frequency synthesizer removes the unwanted sidebands
BSignals are combined in quadrature phase relationship
CMixing products are converted to voltages and subtracted by adder circuits
DVarying quartz crystal characteristics emulated in digital form

37. - E7G02

What is ringing in a filter?

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

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough a neutralizing capacitor
BThrough a tapped coil
CThrough a quartz crystal
DThrough link coupling

39. - E8A05

What of the following instruments would be the most accurate for measuring the RMS voltage of a complex waveform?

SelectAnswer
AA D'Arsonval meter
BA grid dip meter
CAn absorption wave meter
DA true-RMS calculating meter

40. - E8B10

What is frequency division multiplexing?

SelectAnswer
ATwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
BThe transmitted signal is divided into packets of information
CThe transmitted signal jumps from band to band at a predetermined rate
DTwo or more information streams are merged into a baseband, which then modulates the transmitter

41. - E8C04

What technique minimizes the bandwidth of a PSK31 signal?

SelectAnswer
AReed-Solomon character encoding
BUse of sinusoidal data pulses
CUse of trapezoidal data pulses
DZero-sum character encoding

42. - E8D09

What is considered an acceptable maximum IMD level for an idling PSK signal?

SelectAnswer
A-30 dB
B-20 dB
C+15 dB
D+10 dB

43. - E9A13

What term describes station output, taking into account all gains and losses?

SelectAnswer
AApparent power
BPower factor
CEffective radiated power
DHalf-power bandwidth

44. - E9B06

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

SelectAnswer
A45 degrees
B25 degrees
C7.5 degrees
D75 degrees

45. - E9C03

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed in phase?

SelectAnswer
AA Figure-8 broadside to the axis of the array
BOmni-directional
CA Figure-8 end-fire along the axis of the array
DCardioid

46. - E9D11

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

SelectAnswer
AStranded wire
BResistive wire, such as spark plug wire
CSolid wire
DWide flat copper strap

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

SelectAnswer
A50 ohms
B450 ohms
C75 ohms
D62 ohms

48. - E9F01

What is the velocity factor of a transmission line?

SelectAnswer
AThe velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
BThe velocity of the wave in the transmission line divided by the velocity of light in a vacuum
CThe index of shielding for coaxial cable
DThe ratio of the characteristic impedance of the line to the terminating impedance

49. - E9G08

What is the process of normalization with regard to a Smith chart?

SelectAnswer
AReassigning reactance values with regard to the resistance axis
BReassigning resistance values with regard to the reactance axis
CReassigning prime center with regard to the reactance axis
DReassigning impedance values with regard to the prime center

50. - E9H04

What is an advantage of placing a grounded electrostatic shield around a small loop direction-finding antenna?

SelectAnswer
AIt increases signal strength by providing a better match to the feed line
BIt adds capacitive loading, increasing the bandwidth of the antenna
CIt eliminates tracking errors caused by strong out-of-band signals
DIt eliminates unbalanced capacitive coupling to the surroundings, improving the nulls

Figure E5-1

Figure E7-2

Figure E9-2