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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	The exact lower band edge
B	3 kHz above the lower band edge
C	1 kHz above the lower band edge
D	300 Hz above the lower band edge

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	An amateur station transmission made at random without the proper call sign identification
B	A signal transmitted to prevent its detection by any station other than the intended recipient
C	Any transmitted signal that unintentionally interferes with another licensed radio station
D	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C04

What is meant by IARP?

Select	Answer
A	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
B	The internal amateur radio practices policy of the FCC
C	An indication of increased antenna reflected power
D	A forecast of intermittent aurora radio propagation

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
B	An amateur station located more than 50 km above the Earth's surface
C	An amateur station that transmits telemetry consisting of measurements of upper atmosphere
D	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 74%
B	Minimum passing score of 77%
C	Minimum passing score of 80%
D	Minimum passing score of 70%

6. - 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?

Select	Answer
A	420 MHz - 430 MHz
B	53 MHz - 54 MHz
C	222 MHz - 223 MHz
D	440 MHz - 450 MHz

7. - E2A09

What do the terms L band and S band specify with regard to satellite communications?

Select	Answer
A	The 23 centimeter and 13 centimeter bands
B	Which sideband to use
C	FM and Digital Store-and-Forward systems
D	The 2 meter and 70 centimeter bands

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	None; they are allowed on all amateur frequencies
B	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
C	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
D	They are not permitted above 54 MHz

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A standard for submission of electronic contest logs
B	The most common set of contest rules
C	The rules of order for meetings between contest sponsors
D	A method of exchanging information during a contest QSO

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	JT65
B	FSK441
C	PACTOR III
D	Olivia

11. - E2E08

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

Select	Answer
A	AMTOR
B	Hellschreiber
C	RTTY
D	PACTOR

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A fluttery irregular fading
B	The returning echo is several Hertz lower in frequency than the transmitted signal
C	A slow change in the pitch of the CW signal
D	A gradual loss of signal as the Sun rises

13. - E3B09

At what time of year is Sporadic E propagation most likely to occur?

Select	Answer
A	Around the equinoxes, especially the fall equinox
B	Around the solstices, especially the winter solstice
C	Around the solstices, especially the summer solstice
D	Around the equinoxes, especially the spring equinox

14. - E3C11

What does VOACAP software model?

Select	Answer
A	AC current and impedance
B	HF propagation
C	VHF radio propagation
D	AC voltage and impedance

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	Use high quality double shielded coaxial cables to reduce signal losses
B	Match the antenna to the load
C	Attenuate the transmitter output going to the spectrum analyzer
D	All of these choices are correct

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	10 Hz
B	146.52 kHz
C	1465.20 Hz
D	146.52 Hz

17. - E4C10

Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?

Select	Answer
A	6000 Hz
B	100 Hz
C	2400 Hz
D	300 Hz

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
B	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
C	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
D	When the signals from the transmitters are reflected in phase from airplanes passing overhead

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
B	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
C	By installing a noise suppression resistor and a blocking capacitor in both leads
D	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead

20. - E5A03

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

Select	Answer
A	Approximately equal to inductive reactance
B	Approximately equal to circuit resistance
C	High, as compared to the circuit resistance
D	Approximately equal to capacitive reactance

21. - E5B06

What is susceptance?

Select	Answer
A	The inverse of reactance
B	A measure of the efficiency of a transformer
C	The ratio of magnetic field to electric field
D	The magnetic impedance of a circuit

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	Resistive component
B	The difference between the resistive and reactive components
C	The sum of the reactive and resistive components
D	Reactive component

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The amount of current flowing through the conductor
B	The resistance divided by the current
C	The ratio of the current to the resistance
D	The diameter of the conductor

24. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The switching speed of the transistor
B	The breakdown voltage of the base to collector junction
C	The change in collector current with respect to base current
D	The frequency at which the current gain is reduced to 1

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant current drop under conditions of varying voltage
B	A constant voltage drop under conditions of varying current
C	An internal capacitance that varies with the applied voltage
D	A negative resistance region

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A programmable collection of logic gates and circuits in a single integrated circuit
B	An algorithm for simulating logic functions during circuit design
C	Programmable equipment used for testing digital logic integrated circuits
D	A device to control industrial equipment

27. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	Non-linear core hysteresis
B	The skin effect
C	Inter-turn capacitance
D	Inductive kickback

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	TO-220
B	Radial lead
C	Axial lead
D	Surface mount

29. - E6F01

What is photoconductivity?

Select	Answer
A	The conversion of electromotive energy to photon energy
B	The conversion of photon energy to electromotive energy
C	The decreased conductivity of an illuminated semiconductor
D	The increased conductivity of an illuminated semiconductor

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic "1" at its output if all inputs are logic "0"
B	It produces logic "0" at its output if all inputs are logic "1"
C	It produces logic "1" at its output if any or all inputs are logic "1"
D	It only produces logic "0" at its output when all inputs are logic "1"

31. - E7B04

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

Select	Answer
A	At a point where the bias resistor equals the load resistor
B	At a point where the load line intersects the zero bias current curve
C	Approximately half-way between saturation and cutoff
D	Where the load line intersects the voltage axis

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	Pi-networks have fewer components
B	L-networks cannot perform impedance transformation
C	Pi-networks are designed for balanced input and output
D	The Q of Pi-networks can be varied depending on the component values chosen

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	The control element duty cycle is proportional to the line or load conditions
B	It eliminates the need for a pass transistor
C	It has a ramp voltage as its output
D	The conduction of a control element is varied to maintain a constant output voltage

34. - E7E10

How does a diode detector function?

Select	Answer
A	By rectification and filtering of RF signals
B	By mixing signals with noise in the transition region of the diode
C	By breakdown of the Zener voltage
D	By sensing the change of reactance in the diode with respect to frequency

35. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	To reduce excess signal pressure levels
B	Provide access for debugging software
C	Provide incremental signal delays for filter algorithms
D	Select the point at which baseband signals are generated

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The potential between the amplifier input terminals of the op-amp in an open loop condition
B	The differential input voltage needed to bring the open loop output voltage to zero
C	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
D	The output voltage of the op-amp minus its input voltage

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a tapped coil
C	Through a capacitive divider
D	Through link coupling

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

Select	Answer
A	By using a grid dip meter
B	By measuring the voltage with a D'Arsonval meter
C	By using an absorption wave meter
D	By measuring the heating effect in a known resistor

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	Two or more information streams are merged into a baseband, which then modulates the transmitter
B	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
C	The transmitted signal is divided into packets of information
D	The transmitted signal jumps from band to band at a predetermined rate

40. - E8C07

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

Select	Answer
A	15.36 kHz
B	5.76 kHz
C	9.6 kHz
D	4.8 kHz

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	The generation of key clicks
B	Limits data speed
C	More difficult to copy
D	The generation of RF harmonics

42. - E9A16

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?

Select	Answer
A	2000 watts
B	300 watts
C	126 watts
D	317 watts

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region where radiated field strengths are obstructed by objects of reflection
B	The region where radiated power dissipates over a specified time period
C	The region of the ionosphere where radiated power is not refracted
D	The region where the shape of the antenna pattern is independent of distance

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band trap antenna
B	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
C	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
D	A phased array antenna consisting of multiple loops

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	As low as possible on the vertical radiator
B	As close to the transmitter as possible
C	At a voltage node
D	Near the center of the vertical radiator

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To cancel the inductive reactance of the matching network
B	To provide DC isolation between the feed line and the antenna
C	To transform the antenna impedance to a higher value
D	To provide a rejection notch that prevents the radiation of harmonics

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	10 meters
B	6.9 meters
C	24 meters
D	50 meters

48. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Trigonometric functions
B	Impedance and SWR values in transmission lines
C	Beam headings and radiation patterns
D	Satellite azimuth and elevation bearings

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It must be mounted more than 1 wavelength above ground
B	It should be configured as a four-sided loop
C	Its overall length must not exceed 1/4 wavelength
D	It should be one or more wavelengths long

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	Ground reflections and scattering make the field impedance vary with location
B	All of these choices are correct
C	E field and H field radiation intensity peaks can occur at different locations
D	The body reacts to electromagnetic radiation from both the E and H fields