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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz
B	Yes, the DX station initiated the contact
C	Yes, the displayed frequency is within the 80 meter CW band segment
D	No, one of the sidebands of the CW signal will be out of the band

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	An Environmental Assessment must be submitted to the FCC
C	A letter of intent must be filed with the National Audubon Society
D	A proposal must be submitted to the National Park Service

3. - E1C13

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

Select	Answer
A	You must bring a copy of FCC Public Notice DA 11-221
B	You must identify in the official language of the country in which you are operating
C	You must append "/CEPT" to your call sign
D	The U.S. embassy must approve of your operation

4. - E1D08

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

Select	Answer
A	2 meters
B	2 meters and 1.25 meters
C	6 meters, 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 Amateur Extra Class operators
C	Only Technician, General, Advanced or Amateur Extra Class operators
D	Any licensed amateur operator

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 adding the mean anomaly to the orbital inclination
C	By calculations using the Keplerian elements for the specified satellite
D	By subtracting the mean anomaly from the orbital inclination

8. - E2B13

How many lines are commonly used in each frame of an amateur slow-scan color television picture?

Select	Answer
A	180 or 360
B	60 or 100
C	30 or 60
D	128 or 256

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	In the middle of the band, usually 25 kHz above the national calling frequency
B	In the middle of each band, usually on the national calling frequency
C	At the top of each band, usually in a segment reserved for contests
D	In the weak signal segment of the band, with most of the activity near the calling frequency

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
B	All of these choices are correct
C	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
D	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

12. - E3A02

What characterizes libration fading of an EME signal?

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

13. - E3B06

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

Select	Answer
A	80 meters
B	20 meters
C	10 meters
D	6 meters

14. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	Waning sunspot numbers
B	An extreme geomagnetic storm
C	Very low solar activity
D	Moderate solar wind

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

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	The relative time between measurements
B	Relative quality of the data
C	The port or ports at which measurements are made
D	Frequency order of the measurements

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It limits the receiver's ability to receive strong signals
B	It reduces receiver sensitivity
C	It decreases receiver third-order intermodulation distortion dynamic range
D	It can cause strong signals on nearby frequencies to interfere with reception of weak signals

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The difference in dB between the noise floor and the third order intercept point
B	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
C	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor
D	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
B	Your station receiver IF amplifier stage is defective
C	You are receiving sky wave signals from a distant station
D	The broadcast station is transmitting an over-modulated signal

20. - E5A15

Which of the following can increase Q for inductors and capacitors?

Select	Answer
A	Higher self-resonant frequency
B	Lower losses
C	Lower reactance
D	Lower self-resonant frequency

21. - E5B09

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

Select	Answer
A	Voltage and current are in phase
B	Current leads voltage by 90 degrees
C	Voltage leads current by 90 degrees
D	Voltage and current are 180 degrees out of phase

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 3
B	Point 1
C	Point 7
D	Point 8

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In all directions; omni-directional
B	In the same direction as the current
C	In a direction determined by the left-hand rule
D	In a direction opposite to the current

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	6
B	1
C	2
D	3

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Much higher reverse voltage breakdown
B	Less forward voltage drop
C	Enhanced carrier retention time
D	Controlled reverse avalanche voltage

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor in a keying circuit used to reduce key clicks
B	A resistor connected to an op-amp output that only functions when the logic output is false
C	A resistor that insures that an oscillator frequency does not drive lower over time
D	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
C	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
D	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	450 ohms
B	300 ohms
C	50 ohms
D	10 ohms

29. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A device for generating RTTY signals by means of a rotating light source
B	A device which measures the strength of a beam of light using analog to digital conversion
C	A device which detects rotation of a control by interrupting a light source with a patterned wheel
D	A digital encryption device often used to encrypt spacecraft control signals

30. - E7A10

What is a truth table?

Select	Answer
A	A diagram showing logic states when the digital device output is true
B	A table of logic symbols that indicate the logic states of an op-amp
C	A list of inputs and corresponding outputs for a digital device
D	A table of logic symbols that indicate the high logic states of an op-amp

31. - E7B02

What is a Class D amplifier?

Select	Answer
A	A low power amplifier that uses a differential amplifier for improved linearity
B	An amplifier that uses drift-mode FETs for high efficiency
C	A type of amplifier that uses switching technology to achieve high efficiency
D	A frequency doubling amplifier

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The DC voltage applied to the quartz crystal
B	The amplitude of the signals passing through the filter
C	The gain of the RF stage preceding the filter
D	The relative frequencies of the individual crystals

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 balance the low-voltage filament windings
C	To improve output voltage regulation
D	To boost the amount of output current

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
B	The frequency components present in the modulating signal
C	The unmodulated bandwidth of the transmitted signal
D	The lowest frequency band that the transmitter or receiver covers

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

Select	Answer
A	Incoming RF is converted to a control voltage for a voltage controlled oscillator
B	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
C	A switching mixer is used to generate I and Q signals directly from the RF input
D	Software is converted from source code to object code during operation of the receiver

36. - E7G01

What is the typical output impedance of an integrated circuit op-amp?

Select	Answer
A	Very high
B	Very low
C	1000 ohms
D	100 ohms

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

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

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

Select	Answer
A	A sawtooth wave
B	A cosine wave
C	A sine wave
D	A square wave

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It does not depend on the RF carrier frequency
B	It increases as the RF carrier frequency increases
C	It decreases as the RF carrier frequency increases
D	It varies with the square root of the RF carrier frequency

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, a retransmission is requested
B	Special binary codes provide automatic correction
C	Special polynomial codes provide automatic correction
D	If errors are detected, redundant data is substituted

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Phase compandored spread spectrum
B	Frequency hopping
C	Direct sequence
D	Binary phase-shift keying

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The combined losses of the antenna elements and feed line
B	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
C	The specific impedance of the antenna
D	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Calculus differentiation with respect to physical properties
B	Graphical analysis
C	Method of Moments
D	Mutual impedance analysis

44. - E9C06

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

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

45. - E9D06

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

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

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Connect a parallel-resonant LC network across the antenna feed terminals
B	Connect a series-resonant LC network across the antenna feed terminals
C	Use a 50 ohm 1:1 balun between the antenna and feed line
D	Use the universal stub matching technique

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	71 meters
B	10 meters
C	20 meters
D	15 meters

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

Select	Answer
A	In fractions of transmission line electrical wavelength
B	In fractions of antenna electrical wavelength
C	In fractions of transmission line electrical frequency
D	In fractions of antenna electrical frequency

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	All of these choices are correct
B	They must be erected at least 1/2 wavelength above the ground to attain good directivity
C	Low loss coax transmission line is essential for good performance
D	Atmospheric noise is so high that gain over a dipole is not important

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Beryllium Oxide
B	Zinc oxide
C	Uranium Hexafluoride
D	Mica

Figure E5-2

Figure E6-2