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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	No, the sideband will extend beyond the band edge
B	Yes, because you were not the station calling CQ
C	Yes, because the displayed frequency is within the 20 meter band
D	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz

2. - 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?

Select	Answer
A	The amateur station must cease operation
B	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference
C	The amateur station must cease operation on all frequencies below 30 MHz
D	The amateur station must cease operation on all frequencies above 30 MHz

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

Select	Answer
A	Only Extra Class operators may be the control operator of a remote station
B	A control operator need not be present at the control point
C	A control operator must be present at the control point
D	Repeater and auxiliary stations may not be remotely controlled

4. - E1D08

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

Select	Answer
A	2 meters
B	6 meters, 2 meters, and 1.25 meters
C	2 meters and 1.25 meters
D	6 meters and 2 meters

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	Issue the examinee the new or upgrade license
B	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
C	All these choices are correct
D	Photocopy all examination documents and forward them to the FCC for processing

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only General, Advanced or Amateur Extra Class operators
B	Only Technician, General, Advanced or Amateur Extra Class operators
C	Any licensed amateur operator
D	Only Amateur Extra Class operators

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By means of the Doppler data for the specified satellite
B	By subtracting the mean anomaly from the orbital inclination
C	By adding the mean anomaly to the orbital inclination
D	By calculations using the Keplerian elements for the specified satellite

8. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	90
B	120
C	60
D	30

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

Select	Answer
A	Wait 90 minutes or so for the signal degradation to pass
B	Switch to a lower frequency HF band
C	Wait 24 hours before attempting another communication on the band
D	Switch to a higher frequency HF band

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To store digital messages in the satellite for later download by other stations
B	To delay download of telemetry between satellites
C	To relay messages between satellites
D	To upload operational software for the transponder

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	Local
B	ALE can use any type of control
C	Automatic
D	Remote

12. - E3A03

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

Select	Answer
A	When the MUF is above 30 MHz
B	When the Moon is full
C	When the Moon is at perigee
D	When the Moon is at apogee

13. - E3B11

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

Select	Answer
A	Early evening
B	Around sunset
C	Any time
D	Around sunrise

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Decreasing disruption of the geomagnetic field
B	Higher levels of solar UV radiation
C	Increasing disruption of the geomagnetic field
D	An increase in the critical frequency

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Manipulation of time base after trace capture
B	Automatic amplitude and frequency numerical readout
C	All of these choices are correct
D	Storage of traces for future reference

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Temperature coefficient of the logic
B	Decade divider accuracy
C	Input attenuator accuracy
D	Time base accuracy

17. - E4C12

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?

Select	Answer
A	Undesired signals may be heard
B	Thermal-noise distortion
C	Filter ringing
D	Output-offset overshoot

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Oscillator instability and severe audio distortion of all but the strongest received signals
B	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
C	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
D	Cross-modulation of the desired signal and desensitization from strong adjacent signals

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 a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
C	By installing a noise suppression resistor and a blocking capacitor in both leads
D	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It is at a maximum
B	It is at a minimum
C	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
D	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance

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?

Select	Answer
A	14 degrees with the voltage leading the current
B	14 degrees with the voltage lagging the current
C	76 degrees with the voltage lagging the current
D	76 degrees with the voltage leading the current

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Elliptical coordinates
B	Rectangular coordinates
C	Faraday grid
D	Maidenhead grid

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Inductance
B	Malleability
C	Permeability
D	Permittivity

24. - E6A06

What is the beta of a bipolar junction transistor?

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

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	A sub-harmonic pump signal
B	Reverse voltage larger than the RF signal
C	Forward DC bias current
D	Capacitance of an RF coupling capacitor

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

Select	Answer
A	6
B	5
C	2
D	4

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

Select	Answer
A	From less than 20 Hz to approximately 300 MHz
B	From approximately 10 Hz to no more than 3000 kHz
C	From a few kHz to no more than 30 MHz
D	From about 100 kHz to at least 1000 GHz

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	Ball grid array
B	DIP
C	SOT
D	PLCC

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators eliminate the effects of reflected light in the control circuit
B	Optoisolators provide a low impedance link between a control circuit and a power circuit
C	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
D	Optoisolators provide impedance matching between the control circuit and power circuit

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It switches momentarily to the opposite binary state and then returns to its original state after a set time
B	It stores one bit of data in either a 0 or 1 state
C	It produces a continuous square wave oscillating between 1 and 0
D	It maintains a constant output voltage, regardless of variations in the input voltage

31. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

Select	Answer
A	Fixed bias
B	Feedback
C	Load resistors
D	Self bias

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	A special filter that emphasizes image responses
B	A variable bandwidth crystal lattice filter
C	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
D	An automatic notch filter

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To cut down on waste heat generated by the power supply
B	To boost the amount of output current
C	To improve output voltage regulation
D	To balance the low-voltage filament windings

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of an amplifier tank circuit to produce AM signals
B	By varying the tuning of an amplifier tank circuit to produce PM signals
C	By varying the tuning of a microphone preamplifier to produce AM signals
D	By varying the tuning of a microphone preamplifier to produce PM signals

35. - E7F17

What do the letters I and Q in I/Q Modulation represent?

Select	Answer
A	Inactive and Quiescent
B	Instantaneous and Quenched
C	In-phase and Quadrature
D	Instantaneous and Quasi-stable

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

Select	Answer
A	Restrict Q but increase gain
B	Restrict both gain and Q
C	Increase both gain and Q
D	Restrict gain but increase Q

37. - E7H13

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

Select	Answer
A	Use a GPS signal reference
B	Use a rubidium stabilized reference oscillator
C	All of these choices are correct
D	Use a temperature-controlled high Q dielectric resonator

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Phase reversal
B	Sequential sampling
C	Level shifting
D	Harmonic regeneration

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A bandwidth compression technique using Fourier transforms
B	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
C	A digital mode for narrow band, slow speed transmissions
D	A frequency modulation technique which uses non-harmonically related frequencies

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 104 Hz
B	Approximately 26 Hz
C	Approximately 52 Hz
D	Approximately 13 Hz

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It uses one character as a shift code to send numeric and special characters
B	It includes built in error correction features
C	It is possible to transmit both upper and lower case text
D	It contains fewer information bits per character than any other code

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	317 watts
D	126 watts

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

Select	Answer
A	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
B	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
C	Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference
D	Draw two imaginary lines through the ends of the elements and measure the angle between the lines

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It causes increased SWR
B	It reduces low-angle radiation
C	It reduces losses in the radiating portion of the antenna
D	It changes the impedance angle of the matching network

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	No change occurs
B	It is decreased
C	It is increased
D	It becomes flat

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. - E9F11

What impedance does a 1/8 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	A capacitive reactance
B	An inductive reactance
C	The same as the input impedance of the final generator stage
D	The same as the characteristic impedance of the line

48. - E9G01

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

Select	Answer
A	Antenna radiation pattern
B	Impedance along transmission lines
C	Radiation resistance
D	Radio propagation

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

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

Select	Answer
A	Use a calibrated antenna analyzer
B	Use a hand calculator plus Smith-chart equations to calculate the fields
C	Use an antenna modeling program to calculate field strength at accessible locations
D	All of the choices are correct

Figure E6-5

Figure E7-1