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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operators of all the stations in the system
B	The control operator of the packet bulletin board station
C	The control operator of the originating station
D	The control operators of all the stations in the system not authenticating the source from which they accept communications

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

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	3 minutes
B	5 minutes
C	30 seconds
D	10 minutes

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	Two-way radiotelephone transmissions in excess of 1000 feet
B	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
C	Two-way single channel transmissions of data
D	One-way transmission of measurements at a distance from the measuring instrument

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

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must produce full legal output when driven by not more than 5 watts of mean RF input power
B	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
C	It must exhibit a gain of 0 dB or less over its full output range
D	It must be capable of external RF switching between its input and output networks

7. - E2A01

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

Select	Answer
A	From west to east
B	From north to south
C	From south to north
D	From east to west

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	1080
B	30
C	60
D	525

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Operators are permitted to make contacts even if they do not submit a log
B	Interference to other amateurs is unavoidable and therefore acceptable
C	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
D	Every contest requires a signal report in the exchange

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Disconnect
B	Unnumbered Information
C	Acknowledgement
D	Connect

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	PSK31
B	300-baud packet
C	MFSK16
D	170 Hz shift, 45 baud RTTY

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	10 MHz - 14 MHz
B	220 MHz - 450 MHz
C	28 MHz - 148 MHz
D	1.8 MHz - 1.9 MHz

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	Atmospheric noise is lower in the direction of chordal hop propagation
B	The signal experiences less loss along the path compared to normal skip propagation
C	Signals travel faster along ionospheric chords
D	The MUF for chordal hop propagation is much lower than for normal skip propagation

14. - E3C04

What does the value of Bz (B sub Z) represent?

Select	Answer
A	Direction and strength of the interplanetary magnetic field
B	Critical frequency for vertical transmissions
C	Duration of long-delayed echoes
D	Geomagnetic field stability

15. - E4A09

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

Select	Answer
A	One-half the sample rate
B	It depends on how the data is stored internally
C	One-tenth the sample rate
D	The same as the sample rate

16. - E4B15

Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?

Select	Answer
A	The resonant frequency of the circuit
B	The bandwidth of the circuit's frequency response
C	The inductance to capacitance ratio
D	The frequency shift

17. - E4C16

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

Select	Answer
A	Distortion
B	Overload
C	Loss of sensitivity
D	Excess output level

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?

Select	Answer
A	146.88 MHz and 146.34 MHz
B	173.35 MHz and 139.40 MHz
C	146.10 MHz and 147.30 MHz
D	146.34 MHz and 146.61 MHz

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	Received audio in the speech range might have an echo effect
B	FM signals can no longer be demodulated
C	The audio frequency bandwidth of the received signal might be compressed
D	Nearby signals may appear to be excessively wide even if they meet emission standards

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

Select	Answer
A	Conductance
B	Capacitance
C	Resonance
D	Resistance

21. - E5B05

What happens to the magnitude of a reactance when it is converted to a susceptance?

Select	Answer
A	The magnitude of the susceptance is the reciprocal of the magnitude of the reactance
B	It is shifted by 90 degrees
C	The sign is reversed
D	It is unchanged

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By real and imaginary parts
B	By phase angle and amplitude
C	By Y and G values
D	By X and R values

23. - E5D03

What is microstrip?

Select	Answer
A	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
B	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
C	Lightweight transmission line made of common zip cord
D	Miniature coax used for low power applications

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	They are both low impedance
B	They are both high impedance
C	An FET has high input impedance; a bipolar transistor has low input impedance
D	An FET has low input impedance; a bipolar transistor has high input impedance

25. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Excessive inverse voltage
B	Excessive junction temperature
C	Insufficient forward voltage
D	Charge carrier depletion

26. - E6C09

What is a Programmable Logic Device (PLD)?

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

27. - E6D12

What is the definition of saturation in a ferrite core inductor?

Select	Answer
A	The inductor windings are over coupled
B	The ability of the inductor's core to store magnetic energy has been exceeded
C	Adjacent inductors become over-coupled
D	The inductor's voltage rating is exceeded causing a flashover

28. - E6E09

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

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

29. - E6F01

What is photoconductivity?

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

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

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

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	Switching amplifiers use push-pull circuits
B	Switching amplifiers operate at higher voltages
C	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
D	Linear amplifiers have high gain resulting in higher harmonic content

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Extremely flat response over its pass band with gradually rounded stop band corners
B	Extremely sharp cutoff with one or more notches in the stop band
C	Gradual passband rolloff with minimal stop band ripple
D	Gradual passband rolloff with extreme stop band ripple

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A varactor diode
B	A Zener diode
C	An SCR
D	A tunnel diode

34. - E7E10

How does a diode detector function?

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

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Interpolate by a factor of three, then decimate by a factor of four
B	Change the gain by a factor of 3/4
C	Multiply each sample value by a factor of 3/4
D	Add 3 to each input value and subtract 4 from each output value

36. - E7G04

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

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

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a voltage-controlled oscillator and the output waveform
B	The synthesizer frequency limits and frequency values stored in the radio memories
C	The phase relationship between a reference oscillator and the output waveform
D	The amplitude values that represent a sine-wave output

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	1 to 1
B	100 to 1
C	25 to 1
D	2.5 to 1

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	6000
B	2000
C	1/3
D	3

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	4.8 kHz
C	9.6 kHz
D	5.76 kHz

41. - E8D08

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

Select	Answer
A	Baud rate
B	Repeat Request Rate (RRR)
C	Signal to noise ratio
D	Intermodulation Distortion (IMD)

42. - E9A08

What is meant by antenna bandwidth?

Select	Answer
A	The angle formed between two imaginary lines drawn through the element ends
B	The angle between the half-power radiation points
C	The frequency range over which an antenna satisfies a performance requirement
D	Antenna length divided by the number of elements

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	18 dB
B	36 dB
C	14 dB
D	24 dB

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It changes the radiation pattern from horizontal to vertical polarization
B	It changes the radiation pattern from bidirectional to unidirectional
C	It reflects the standing waves on the antenna elements back to the transmitter
D	It decreases the ground loss

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance decreases and the capacitive reactance decreases
B	The radiation resistance increases and the capacitive reactance increases
C	The radiation resistance increases and the capacitive reactance decreases
D	The radiation resistance decreases and the capacitive reactance increases

46. - E9E05

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

Select	Answer
A	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
B	The driven element resonance must be lower than the operating frequency
C	The driven element reactance must be capacitive
D	The driven element reactance must be inductive

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

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Points with constant reactance
B	SWR
C	Points with constant resistance
D	Frequency

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	A fixed receiving station plots three headings to the signal source
B	Antenna headings from several different receiving locations are used to locate the signal source
C	The geometric angles of sky waves from the source are used to determine its position
D	A fixed receiving station uses three different antennas to plot the location of the signal source

50. - E0A10

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

Select	Answer
A	Polytetrafluroethylene
B	Polychlorinated Biphenyls
C	Polyethylene
D	Polymorphic silicon

Figure E9-1