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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	Yes, because the displayed frequency is within the 20 meter band
B	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz
C	No, the sideband will extend beyond the band edge
D	Yes, because you were not the station calling CQ

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	A signal transmitted to prevent its detection by any station other than the intended recipient
B	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
C	Any transmitted signal that unintentionally interferes with another licensed radio station
D	An amateur station transmission made at random without the proper call sign identification

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	CEPT agreement
B	IARP agreement
C	All of these choices are correct
D	ITU reciprocal license

4. - E1D04

What is an Earth station in the amateur satellite service?

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

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	Providing amateur operator license examination preparation training materials
B	Preparing, processing, administering and coordinating an examination for an amateur radio license
C	Teaching an amateur operator license examination preparation course
D	No expenses are authorized for reimbursement

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide additional spectrum for personal use
B	To allow regular operation on Land Mobile channels
C	To provide temporary operation while awaiting normal licensing
D	To provide for experimental amateur communications

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From west to east
B	From south to north
C	From east to west
D	From north to south

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Elapsed time
B	Specific tone frequencies
C	Specific tone amplitudes
D	A two-tone signal

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Special event contacts between stations in the U.S.
B	Repeater contacts between U.S. club members
C	Contacts between a U.S. station and a non-U.S. station
D	Contacts using tactical call signs

10. - E2D10

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

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

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	ALE can use any type of control
B	Local
C	Remote
D	Automatic

12. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Mountain ranges
B	Urban areas
C	Forests
D	Bodies of water

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become phase-locked
B	They become elliptically polarized
C	They are bent toward the magnetic poles
D	Their polarization is randomly modified

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class A
B	Class B
C	Class M
D	Class X

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Automatic amplitude and frequency numerical readout
B	Manipulation of time base after trace capture
C	Storage of traces for future reference
D	All of these choices are correct

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It is relatively immune to drift in the signal generator source
B	It can display results directly in Smith chart format
C	It is very precise in obtaining a signal null
D	It provides an excellent match under all conditions

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	4.8 kHz
B	1 kHz
C	4.2 kHz
D	2.4 kHz

18. - E4D01

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

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

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A whining type noise that continually pulses off and on
B	A loud AC hum in the audio output of your station receiver
C	The appearance of unstable modulated or unmodulated signals at specific frequencies
D	A clicking noise at intervals of a few seconds

20. - E5A10

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

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

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

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 8
D	Point 7

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Inductance
B	Malleability
C	Permeability
D	Permittivity

24. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter voltage of approximately 6 to 7 volts
B	Base-to-emitter resistance of approximately 6 to 7 ohms
C	Base-to-emitter voltage of approximately 0.6 to 0.7 volts
D	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a constant voltage source
B	As a high voltage rectifier
C	As an RF detector
D	As a constant current source

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

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

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores confine most of the magnetic field within the core material
B	Toroidal cores make it easier to couple the magnetic energy into other components
C	Toroidal cores exhibit greater hysteresis
D	Toroidal cores have lower Q characteristics

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Stripped lead
B	Surface mount
C	Virtual lead mounting
D	Direct soldering

29. - E6F10

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

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

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It stores one bit of data in either a 0 or 1 state
B	It maintains a constant output voltage, regardless of variations in the input voltage
C	It produces a continuous square wave oscillating between 1 and 0
D	It switches momentarily to the opposite binary state and then returns to its original state after a set time

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. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Higher efficiency
B	Greater transformation range
C	Lower losses
D	Greater harmonic suppression

33. - E7D08

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

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

34. - E7E06

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

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

35. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	To reduce excess signal pressure levels
B	Provide incremental signal delays for filter algorithms
C	Select the point at which baseband signals are generated
D	Provide access for debugging software

36. - E7G03

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

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

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Frequency synthesis, FM demodulation
B	Photovoltaic conversion, optical coupling
C	Comparison of two digital input signals, digital pulse counter
D	Wide-band AF and RF power amplification

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	All of these choices are correct
C	Digital signals can be regenerated multiple times without error
D	Digital signals always occupy a narrower bandwidth

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal jumps from band to band at a predetermined rate
B	Two or more information streams are merged into a baseband, which then modulates the transmitter
C	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
D	The transmitted signal is divided into packets of information

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	4.8 kHz
B	5.76 kHz
C	9.6 kHz
D	15.36 kHz

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

Select	Answer
A	A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
B	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
C	The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It increases geometrically
B	It increases arithmetically
C	It is essentially unaffected
D	It decreases

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	Next Element Comparison
B	Numerical Electromagnetic Code
C	Numeric Electrical Computation
D	National Electrical Code

44. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

Select	Answer
A	Cardioid
B	A figure-8 broadside to the axis of the array
C	A figure-8 oriented along the axis of the array
D	Omni-directional

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	It becomes flat
C	It is increased
D	No change occurs

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	Double-bazooka match
D	Gamma match

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

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

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Prime axis
B	Impedance axis
C	Polar axis
D	Reactance axis

49. - E9H11

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

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

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	Uranium Hexafluoride
B	Mica
C	Beryllium Oxide
D	Zinc oxide

Figure E5-2

Figure E7-3

Figure E9-3