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

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	100 watts PEP effective radiated power relative to an isotropic radiator
B	50 watts PEP effective radiated power relative to an isotropic radiator
C	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
D	50 watts PEP effective radiated power relative to a dipole

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You must obtain a construction permit from the airport zoning authority
B	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
C	You must file an Environmental Impact Statement with the EPA before construction begins
D	No special rules apply if your antenna structure will be less than 300 feet in height

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	The U.S. embassy must approve of your operation
C	You must append "/CEPT" to your call sign
D	You must identify in the official language of the country in which you are operating

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

Select	Answer
A	Any class with appropriate operator privileges
B	All except Technician Class
C	Only General, Advanced or Amateur Extra Class
D	Only Amateur Extra Class

5. - E1E06

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

Select	Answer
A	The VEC coordinating the session
B	Each administering VE
C	The FCC
D	The VE session manager

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
B	The transmission must not be used to obscure the meaning of any communication
C	All of these choices are correct
D	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Doppler shift of beacon signals
B	Radar
C	Bandwidth compressed LORAN
D	APRS

8. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

Select	Answer
A	By scanning odd numbered lines in one field and even numbered lines in the next
B	By scanning each field from bottom to top
C	By scanning two fields simultaneously
D	By scanning lines from left to right in one field and right to left in the next

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
B	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
C	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
D	The acceptable practice of manually posting the call signs of stations on a spotting network

10. - E2D08

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

Select	Answer
A	Acknowledgement
B	Connect
C	Unnumbered Information
D	Disconnect

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	PSK31
B	MFSK
C	Winlink
D	RTTY

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 gradual loss of signal as the Sun rises
D	A slow change in the pitch of the CW signal

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	160 meters to 10 meters
B	160 meters to 40 meters
C	6 meters to 2 meters
D	30 meters to 10 meters

14. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the Sun will cause disturbed conditions?

Select	Answer
A	Eastward
B	Southward
C	Northward
D	Westward

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

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High impedance input
B	High reluctance input
C	Low reluctance input
D	Low impedance input

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 decreases receiver third-order intermodulation distortion dynamic range
C	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
D	It reduces receiver sensitivity

18. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

Select	Answer
A	Signals less than 40 dBm will not generate audible third-order intermodulation products
B	The receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
C	A pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
D	A pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal

19. - E4E15

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

Select	Answer
A	Tying all ground connections to a common point resulting in differential mode currents in the shield
B	Low inductance ground connections at both ends of the shield
C	Common mode currents on the shield and conductors
D	Use of braided shielding material

20. - E5A06

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

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

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	One discharge period
B	One time constant
C	An exponential discharge rate of one
D	A discharge factor of one

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	Omega
B	X
C	-jX
D	+jX

23. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	To increase the thermal time constant
B	All of these choices are correct
C	To avoid unwanted inductive reactance
D	To maintain component lifetime

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	P-type
B	Superconductor-type
C	Bipolar-type
D	N-type

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

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	Its simplicity results in much less expensive devices than standard CMOS
B	It is totally immune to electrostatic damage
C	All of these choices are correct
D	It has the high input impedance of CMOS and the low output impedance of bipolar transistors

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Excitation current
B	Stabilizing current
C	Direct current
D	Magnetizing current

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. - E6F07

What is a solid state relay?

Select	Answer
A	A device that uses semiconductors to implement the functions of an electromechanical relay
B	A mechanical relay that latches in the on or off state each time it is pulsed
C	A passive delay line
D	A relay using transistors to drive the relay coil

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	An XOR gate
B	A flip-flop
C	A multiplexer
D	An OR gate

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they invert the sidebands causing distortion
B	Because they maintain the sidebands, thus causing multiple duplicate signals
C	Because they are relatively close in frequency to the desired signal
D	Because they are relatively far in frequency from the desired signal

32. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Select	Answer
A	Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
B	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
C	An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
D	A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Grounded emitter amplifier
B	Emitter follower
C	Linear voltage regulator
D	Switching voltage regulator

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

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	A notch filter
B	An elliptical filter
C	An adaptive filter
D	A Hilbert-transform filter

36. - E7G03

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

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

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A direct digital synthesizer
B	A diode-switching matrix synthesizer
C	A phase locked loop synthesizer
D	A hybrid synthesizer

38. - E8A06

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

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

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
B	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
C	Two or more signals are quadrature modulated to increase bandwidth efficiency
D	Two or more signals are arranged to share discrete time slots of a data transmission

40. - E8C05

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

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

41. - E8D04

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

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

42. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

Select	Answer
A	Transmission-line length
B	Antenna height, conductor length/diameter ratio and location of nearby conductive objects
C	Sunspot activity and time of day
D	The settings of an antenna tuner at the transmitter

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	24 dB
C	14 dB
D	36 dB

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The horizontal beam width decreases with height
B	The horizontal beam width increases with height
C	The main lobe takeoff angle increases with increasing height
D	The main lobe takeoff angle decreases with increasing height

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to a metal water pipe
B	A 50 ohm resistor connected to ground
C	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
D	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	Hairpin match
B	All of these choices are correct
C	Gamma match
D	Double-bazooka match

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	The same as the generator output impedance
B	Very low impedance
C	Very high impedance
D	The same as the characteristic impedance of the transmission line

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Free space radiation directivity chart
B	Smith chart
C	Elevation angle radiation pattern chart
D	Azimuth angle radiation pattern chart

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It prevents receiver overload which could make it difficult to determine peaks or nulls
B	It compensates for the effects of an isotropic antenna, thereby improving directivity
C	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
D	It narrows the bandwidth of the received signal to improve signal to noise ratio

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Hearing loss caused by high voltage corona discharge
B	Blood clotting from the intense magnetic field
C	Ingestion of ozone gas from the cooling system
D	Localized heating of the body from RF exposure in excess of the MPE limits

Figure E7-3

Figure E9-1

Figure E9-3