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

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1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

Select	Answer
A	Yes, because the DX station initiated the contact
B	Yes, because the displayed frequency is within the 75 meter phone band segment
C	No, the sideband will extend beyond the edge of the phone band segment
D	No, U.S. stations are not permitted to use phone emissions below 3.610 MHz

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 file an Environmental Impact Statement with the EPA before construction begins
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 obtain a construction permit from the airport zoning authority
D	No special rules apply if your antenna structure will be less than 300 feet in height

3. - E1C12

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

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

4. - E1D01

What is the definition of the term telemetry?

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

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 74%
B	Minimum passing score of 70%
C	Minimum passing score of 77%
D	Minimum passing score of 80%

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	10 W
B	1.5 W
C	1 W
D	1.5 kW

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geomagnetic
B	Geostationary
C	LEO
D	HEO

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
B	None; they are allowed on all amateur frequencies
C	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
D	They are not permitted above 54 MHz

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Multiple Frequency Shift Keying in the 10 GHz band
B	Store and forward on the 440 MHz band
C	Spread spectrum in the 2.4 GHz band
D	Frequency division multiplex in the 24 GHz band

10. - E2D02

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

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

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	Rain droplets must be within the E layer
B	Rain droplets must be electrically charged
C	All of these choices are correct
D	The rain must be within radio range of both stations

13. - E3B08

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

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

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to aurora refraction
B	E-region skip
C	Downward bending due to density variations in the atmosphere
D	D-region skip

15. - E4A14

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

Select	Answer
A	It prevents oscillation in a low-frequency counter circuit
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 multiplies a higher frequency signal so a low-frequency counter can display the operating frequency

16. - E4B11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Select	Answer
A	Loosely couple the antenna and a dummy load to the analyzer
B	Loosely couple the analyzer near the antenna base
C	Connect the analyzer via a high-impedance transformer to the antenna
D	Connect the antenna feed line directly to the analyzer's connector

17. - E4C15

What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Select	Answer
A	Detector noise
B	Atmospheric noise
C	Induction motor noise
D	Receiver front-end noise

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

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

Select	Answer
A	All of these choices are correct
B	The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
C	The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
D	The interfering signal may drift slowly across the HF spectrum

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

Select	Answer
A	Reactance of either the inductance or capacitance divided by the resistance
B	Reactance of the inductance multiplied by the reactance of the capacitance
C	Reactance of either the inductance or capacitance multiplied by the resistance
D	Resistance divided by the reactance of either the inductance or capacitance

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	Y
B	G
C	B
D	X

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

Select	Answer
A	Point 2
B	Point 6
C	Point 5
D	Point 4

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	1600 watts
B	1000 watts
C	600 watts
D	200 watts

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Donor impurity
B	Insulator impurity
C	Acceptor impurity
D	N-type impurity

25. - E6B13

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

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

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A logic family based on bismuth CMOS devices
B	An integrated circuit logic family using both bipolar and CMOS transistors
C	A FET logic family based on bimetallic semiconductors
D	A logic device with two CMOS circuits per package

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Ferrite beads
B	Butterworth filters
C	Electrolytic capacitors
D	Steel-core toroids

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	SOT
B	DIP
C	Ball grid array
D	PLCC

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Selenium
B	Cadmium Sulfide
C	Copper oxide
D	Silicon

30. - E7A11

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

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

31. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common base
B	Common collector
C	Common emitter
D	Emitter follower

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a notch filter
B	It is a high-pass filter
C	It is a low-pass filter
D	It is a band-pass filter

33. - E7D08

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

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

34. - E7E10

How does a diode detector function?

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

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Reference voltage level and sample width in bits
B	Sample clock phase noise
C	Data storage transfer rate
D	Missing codes and jitter

36. - E7G01

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

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

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Bias the crystal at a specified voltage
B	Provide the crystal with a specified parallel capacitance
C	Bias the crystal at a specified current
D	Provide the crystal with a specified parallel inductance

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Differential analysis
B	Vector analysis
C	Fourier analysis
D	Numerical analysis

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	1/3
C	2000
D	3

40. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	1.0 kHz
B	0.5 kHz
C	0.1 Hz
D	0.3 kHz

41. - E8D04

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

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

42. - E9A18

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Power factor
B	Apparent power
C	Half-power bandwidth
D	Effective radiated power

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	45 degrees
B	7.5 degrees
C	25 degrees
D	75 degrees

44. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The vertical angle increases
B	The lobes align more in the direction of the wire
C	The front-to-back ratio decreases
D	The lobes become more perpendicular to the wire

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The frequency response is widened over the whole frequency band
B	The front-to-back ratio increases
C	The SWR is reduced
D	The front-to-back ratio decreases

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The delta match
B	The gamma match
C	The omega match
D	The stub match

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

Select	Answer
A	The line length
B	The center conductor resistivity
C	The termination impedance
D	Dielectric materials used in the line

48. - E9G05

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

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

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It should be one or more wavelengths long
B	It should be configured as a four-sided loop
C	Its overall length must not exceed 1/4 wavelength
D	It must be mounted more than 1 wavelength above ground

50. - E0A11

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

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

Figure E5-2

Figure E7-1

Figure E7-3

Figure E9-2

Figure E9-3