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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	1.5 kHz
B	2.8 kHz
C	60 Hz
D	170 Hz

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

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Business-related messages for non-profit organizations
B	Communications incidental to the purpose of the amateur service and remarks of a personal nature
C	All of these choices are correct
D	Messages intended for connection to users of the maritime satellite service

4. - E1D08

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

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

5. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Friends of the VE
B	Employees of the VE
C	Relatives of the VE as listed in the FCC rules
D	All of these choices are correct

6. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and west of the U.S. Atlantic coastline
B	A line roughly parallel to and east of the U.S. Pacific coastline
C	A line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
D	A line roughly parallel to and south of the U.S.-Canadian border

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	435 MHz - 438 MHz
B	144 MHz - 146 MHz
C	50.0 MHz - 50.2 MHz
D	29.5 MHz - 29.7 MHz

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

Select	Answer
A	Vestigial sideband provides high frequency emphasis to sharpen the picture
B	The vestigial sideband contains chroma information
C	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
D	The vestigial sideband carries the audio information

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	Every contest requires a signal report in the exchange
C	Interference to other amateurs is unavoidable and therefore acceptable
D	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station

10. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	Short transmission with rapidly repeated call signs and signal reports
B	15 second timed transmission sequences with stations alternating based on location
C	Use of high speed CW or digital modes
D	All of these choices are correct

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave of alternating current, in the core of an electromagnet
B	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
C	A wave consisting of two electric fields at parallel right angles to each other
D	A wave consisting of two magnetic fields at right angles to each other

13. - E3B08

What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?

Select	Answer
A	Sporadic-E
B	Transequatorial
C	Gray-line
D	Long-path

14. - E3C04

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

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

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
B	It amplifies low level signals for more accurate counting
C	It divides a higher frequency signal so a low-frequency counter can display the input frequency
D	It prevents oscillation in a low-frequency counter circuit

16. - E4B01

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

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

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Frequency discrimination
B	Cross-modulation interference
C	Capture effect
D	Desensitization

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To increase rejection of unwanted signals
B	To store often-used frequencies
C	To provide a range of AGC time constants
D	To allow selection of the optimum RF amplifier device

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

Select	Answer
A	Heterodyne interference
B	Broadband white noise
C	All of these choices are correct
D	Ignition noise

20. - E5A02

What is resonance in an electrical circuit?

Select	Answer
A	The highest frequency that will pass current
B	The frequency at which the capacitive reactance equals the inductive reactance
C	The lowest frequency that will pass current
D	The frequency at which the reactive impedance equals the resistive impedance

21. - E5B09

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

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

22. - E5C02

How are impedances described in polar coordinates?

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

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated in the formation of inductive and capacitive fields
B	It is dissipated as kinetic energy in the circuit
C	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
D	It is dissipated as heat in the circuit

24. - E6A13

What do the initials CMOS stand for?

Select	Answer
A	Complementary Mica-Oxide Silicon
B	Common Mode Organic Silicon
C	Common Mode Oscillating System
D	Complementary Metal-Oxide Semiconductor

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Inductive bias
B	Forward bias
C	Zero bias
D	Reverse bias

26. - E6C03

What is tri-state logic?

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

27. - E6D12

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

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

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

Select	Answer
A	To provide a low-pass frequency response
B	Better dissipation of heat
C	High-voltage insulating ability
D	Enhanced sensitivity to light

29. - E6F05

Which describes an optical shaft encoder?

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

30. - E7A11

What type of logic defines "1" as a high voltage?

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

31. - E7B01

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

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

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	The Q of Pi-networks can be varied depending on the component values chosen
B	L-networks cannot perform impedance transformation
C	Pi-networks have fewer components
D	Pi-networks are designed for balanced input and output

33. - E7D12

What is the drop-out voltage of an analog voltage regulator?

Select	Answer
A	Minimum input-to-output voltage required to maintain regulation
B	Maximum amount that the output voltage may decrease at rated load
C	Minimum input voltage for rated power dissipation
D	Maximum amount that the output voltage drops when the input voltage is varied over its specified range

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A de-emphasis network
B	An audio prescaler
C	A pre-emphasis network
D	A heterodyne suppressor

35. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A crystal-lattice filter
B	An adaptive filter
C	A phase-inverting filter
D	A Hilbert-transform filter

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	For smoothing power supply output
B	As a low-pass filter used between a transmitter and a transmission line
C	As a high-pass filter used to block RFI at the input to receivers
D	As an audio filter in a receiver

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 hybrid synthesizer
C	A phase locked loop synthesizer
D	A diode-switching matrix synthesizer

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	All of these choices are correct
B	Data
C	Human speech
D	Video signals

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. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Excess 3 code
C	Extended Binary Coded Decimal Interchange Code
D	Gray code

41. - E8D08

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

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

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(radiation resistance / transmission resistance) x 100 per cent
B	(effective radiated power / transmitter output) x 100 percent
C	(total resistance / radiation resistance) x 100 per cent
D	(radiation resistance / total resistance) x 100 per cent

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	24 dB
B	28 dB
C	15 dB
D	3 dB

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A wideband vertical antenna constructed from precisely tapered aluminum tubing
B	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
C	An end fed folded dipole antenna
D	A portable antenna erected using two push support poles

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth decreases
B	Gain is reduced
C	SWR bandwidth increases
D	More common-mode current is present on the feed line

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
B	It allows single-band antennas to operate on other bands
C	It makes sure the antenna has a low-angle radiation pattern
D	It ensures that each driven element operates in concert with the others to create the desired antenna pattern

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Lower loss
B	Lower velocity factor
C	Smaller reflection coefficient
D	Higher SWR

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning reactance values with regard to the resistance axis
B	Reassigning resistance values with regard to the reactance axis
C	Reassigning impedance values with regard to the prime center
D	Reassigning prime center with regard to the reactance axis

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It is non-rotatable
B	It has a bidirectional pattern
C	It receives equally well in all directions
D	It is practical for use only on VHF bands

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Make sure signals from your station are less than the uncontrolled MPE limits
B	Advise your neighbors of the results of your tests
C	Make sure signals from your station are less than the controlled MPE limits
D	You need only evaluate exposure levels on your own property

Figure E9-2