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

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 43 dB below
B	At least 53 dB below
C	At least 73 dB below
D	At least 63 dB below

3. - E1C04

What is meant by IARP?

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

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station that is not able to communicate using amateur satellites
B	Any amateur station on the surface of the Earth
C	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
D	An amateur station that transmits telemetry consisting of measurement of upper atmosphere

5. - E1E06

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

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

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 exhibit a gain of 0 dB or less over its full output range
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 be capable of external RF switching between its input and output networks
D	It must produce full legal output when driven by not more than 5 watts of mean RF input power

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. - E2B03

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

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

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
B	To improve operating efficiency by reducing interference
C	To separate the calling stations from the DX station
D	All of these choices are correct

10. - E2D14

What is one advantage of using JT65 coding?

Select	Answer
A	Permits fast-scan TV transmissions over narrow bandwidth
B	The ability to decode signals which have a very low signal to noise ratio
C	Easily copied by ear if necessary
D	Uses only a 65 Hz bandwidth

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	Your transmit frequency is incorrect
B	All of these choices are correct
C	Another station you are unable to hear is using the frequency
D	The protocol version you are using is not the supported by the digital station

12. - E3A14

From the contiguous 48 states, in which approximate direction should an antenna be pointed to take maximum advantage of aurora propagation?

Select	Answer
A	West
B	North
C	South
D	East

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Noon
B	Afternoon or early evening
C	Late at night
D	Morning

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The ratio of X-Ray flux to radio flux, correlated to sunspot number
B	UV emissions at 304 angstroms, correlated to solar flux index
C	The solar emission at 304 GHz, correlated to X-Ray flare levels
D	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity

15. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	Antenna analyzers display a time-varying representation of the modulation envelope
B	All of these choices are correct
C	Antenna analyzers do not need an external RF source
D	Antenna analyzers automatically tune your antenna for resonance

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	Cross modulation occurs
B	Intermodulation distortion occurs
C	A less accurate reading results
D	Harmonics are generated

17. - E4C10

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

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

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 level of an incoming signal which will cause 1 dB of gain compression
B	The difference in dB between the noise floor and the third order intercept point
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. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	An electrical-sparking signal
B	A common-mode signal at the frequency of the radio transmitter
C	Harmonics of the AC power line frequency
D	A differential-mode signal at the AC power line frequency

20. - E5A04

What is the magnitude of the impedance of a circuit with a resistor, an inductor and a capacitor all in parallel, at resonance?

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

21. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?

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

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

Select	Answer
A	A positive real part
B	A negative real part
C	A negative phase angle
D	A positive phase angle

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	1.73
B	0.5
C	1.414
D	0.866

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. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	1
B	6
C	7
D	5

26. - E6C03

What is tri-state logic?

Select	Answer
A	Low power logic devices designed to operate at 3 volts
B	Logic devices that utilize ternary math
C	Logic devices with 0, 1, and high impedance output states
D	Proprietary logic devices manufactured by Tri-State Devices

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

28. - E6E09

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

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

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	A heavy metal
B	An ordinary metal
C	A liquid semiconductor
D	A crystalline semiconductor

30. - E7A12

What type of logic defines "0" as a high voltage?

Select	Answer
A	Reverse Logic
B	Assertive Logic
C	Positive Logic
D	Negative logic

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

Select	Answer
A	Exactly 180 degrees
B	More than 180 degrees but less than 360 degrees
C	Less than 180 degrees
D	The entire cycle

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Pi-L
B	Pi
C	Omega
D	Cascode

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	The resistance of a control element is varied in direct proportion to the line voltage or load current
B	It is generally less efficient than a linear regulator
C	The controlled device's duty cycle is changed to produce a constant average output voltage
D	It gives a ramp voltage at its output

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	To reduce impulse noise reception
B	To remove third-order distortion products
C	For higher efficiency
D	For compatibility with transmitters using phase modulation

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At the same rate as the highest frequency component of the signal
B	At four times the rate of the highest frequency component of the signal
C	At twice the rate of the highest frequency component of the signal
D	At half the rate of the highest frequency component of the signal

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	0.23 volts
B	2.3 volts
C	-0.23 volts
D	-2.3 volts

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Broadband noise
B	Digital conversion noise
C	Spurious signals at discrete frequencies
D	Nyquist limit noise

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Improve accuracy by removing out of sequence codes from the input
B	All of these choices are correct
C	Remove harmonics from the output caused by the discrete analog levels generated
D	Lower the input bandwidth to increase the effective resolution

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. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is twice the symbol rate
B	Symbol rate is only used for packet-based modes
C	Baud is only used for RTTY
D	They are the same

41. - E8D08

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

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

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

Select	Answer
A	To calculate the front-to-back ratio of the antenna
B	To measure the near-field radiation density from a transmitting antenna
C	To calculate the front-to-side ratio of the antenna
D	To match impedances in order to minimize standing wave ratio on the transmission line

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	1
B	3
C	7
D	4

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A type of ground-plane antenna
B	A dipole one-quarter wavelength long
C	A dipole configured to provide forward gain
D	A dipole consisting of one wavelength of wire forming a very thin loop

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

Select	Answer
A	It radiates the harmonics and fundamental equally well
B	It might radiate harmonics
C	It must be neutralized
D	It is too sharply directional at lower frequencies

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The delta matching system
B	The stub matching system
C	The gamma matching system
D	The omega matching system

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	6.9 meters
B	10 meters
C	50 meters
D	24 meters

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The reactance axis
B	The resistance axis
C	The current axis
D	The voltage axis

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	A very sharp single null
B	High-radiation angle
C	A very sharp peak
D	Broad band response

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	The body reacts to electromagnetic radiation from both the E and H fields
C	E field and H field radiation intensity peaks can occur at different locations
D	All of these choices are correct

Figure E6-2

Figure E6-3

Figure E7-4

Figure E9-2

Figure E9-3