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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use
B	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
C	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
D	Its operation must be approved by the master of the ship or the pilot in command of the aircraft

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	1 mile
B	10 miles
C	3 miles
D	30 miles

3. - E1C01

What is a remotely controlled station?

Select	Answer
A	A station operating under automatic control
B	A station controlled indirectly through a control link
C	A station controlled by someone other than the licensee
D	A station operated away from its regular home location

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Any amateur station, subject to the privileges of the class of operator license held by the control operator
B	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
C	Only those of Amateur Extra Class operators
D	Only those of General, Advanced or Amateur Extra Class operators

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
B	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
C	The prospective VE obtains accreditation from the FCC
D	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Technician, General, Advanced or Amateur Extra Class operators
B	Any licensed amateur operator
C	Only General, Advanced or Amateur Extra Class operators
D	Only Amateur Extra Class operators

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The time it takes for a satellite to travel from perigee to apogee
B	The point of maximum height of a satellite's orbit
C	The point of minimum height of a satellite's orbit
D	The time it takes for a satellite to complete one revolution around the Earth

8. - E2B15

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

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

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send your full call sign once or twice
B	Send your full call sign and grid square
C	Send only the last two letters of your call sign until you make contact
D	Send the call sign of the DX station three times, the words "this is", then your call sign three times

10. - E2D13

What type of modulation is used for JT65 contacts?

Select	Answer
A	Multi-tone AFSK
B	RTTY
C	IEEE 802.11
D	PSK

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Fatal Error Correction
B	First Error Correction
C	Final Error Correction
D	Forward Error Correction

12. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

Select	Answer
A	500 miles, if the Moon is at perigee
B	12,000 miles, if the Moon is visible by both stations
C	2000 miles, if the Moon is at apogee
D	5000 miles, if the Moon is at perigee

13. - E3B03

What is the best time of day for transequatorial propagation?

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

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	Southward
B	Eastward
C	Northward
D	Westward

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A time-domain reflectometer
B	A spectrum analyzer
C	A logic analyzer
D	A wattmeter

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
B	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
C	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
D	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed

17. - E4C05

What does a value of -174 dBm/Hz represent with regard to the noise floor of a receiver?

Select	Answer
A	The minimum detectable signal as a function of receive frequency
B	The noise figure of a 1 Hz bandwidth receiver
C	The galactic noise contribution to minimum detectable signal
D	The theoretical noise at the input of a perfect receiver at room temperature

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	A large increase in background noise
B	The desired signal can no longer be heard
C	The off-frequency unwanted signal is heard in addition to the desired signal
D	A reduction in apparent signal strength

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Common-mode current
B	Differential-mode current
C	Reactive current only
D	Return current

20. - E5A02

What is resonance in an electrical circuit?

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

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	Y
B	B
C	G
D	X

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 8
B	Point 3
C	Point 7
D	Point 1

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Permittivity
B	Inductance
C	Malleability
D	Permeability

24. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The breakdown voltage of the base to collector junction
B	The switching speed of the transistor
C	The frequency at which the current gain is reduced to 1
D	The change in collector current with respect to base current

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant voltage drop under conditions of varying current
B	A constant current drop under conditions of varying voltage
C	An internal capacitance that varies with the applied voltage
D	A negative resistance region

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

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

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

Select	Answer
A	Trimmer capacitor
B	Clipper capacitor
C	Snubber capacitor
D	Feedback capacitor

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Silicon dioxide
B	Gallium nitride
C	Silicon
D	Silicon nitride

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 relay using transistors to drive the relay coil
C	A passive delay line
D	A mechanical relay that latches in the on or off state each time it is pulsed

30. - E7A10

What is a truth table?

Select	Answer
A	A list of inputs and corresponding outputs for a digital device
B	A table of logic symbols that indicate the high logic states of an op-amp
C	A diagram showing logic states when the digital device output is true
D	A table of logic symbols that indicate the logic states of an op-amp

31. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

Select	Answer
A	Tune both the input and output for maximum power
B	Use a phase inverter in the output filter
C	Tune the stage for maximum SWR
D	Install parasitic suppressors and/or neutralize the stage

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A Butterworth filter
B	An active LC filter
C	A passive op-amp filter
D	A Chebyshev filter

33. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-3?

Select	Answer
A	To provide fixed DC bias for Q1
B	To self-resonate at the hum frequency
C	It bypasses hum around D1
D	It is a brute force filter for the output

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	The sum, difference and square root of the input frequencies
B	1.414 and 0.707 times the input frequency
C	Two and four times the original frequency
D	The two input frequencies along with their sum and difference frequencies

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters are easier to implement for a given set of passband rolloff requirements
B	FIR filters can respond faster to impulses
C	FIR filters delay all frequency components of the signal by the same amount
D	All of these choices are correct

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	24
B	94
C	47
D	0.21

37. - E7H13

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

Select	Answer
A	Use a temperature-controlled high Q dielectric resonator
B	Use a GPS signal reference
C	Use a rubidium stabilized reference oscillator
D	All of these choices are correct

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	Very high speed allows digitizing high frequencies
B	Very low power consumption decreases frequency drift
C	All of these choices are correct
D	Immunity to out of sequence coding reduces spurious responses

39. - E8B10

What describes frequency division multiplexing?

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

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	Special binary codes provide automatic correction
B	If errors are detected, redundant data is substituted
C	If errors are detected, a retransmission is requested
D	Special polynomial codes provide automatic correction

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Excessive transmit audio levels
B	Bit errors in the modem
C	Ground loops
D	Excessive numbers of retries

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Radiation resistance plus space impedance
B	Radiation resistance plus transmission resistance
C	Transmission-line resistance plus radiation resistance
D	Radiation resistance plus ohmic resistance

43. - E9B03

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-side ratio?

Select	Answer
A	14 dB
B	24 dB
C	12 dB
D	18 dB

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
B	A phased array antenna consisting of multiple loops
C	A multi-band trap antenna
D	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To lower the losses
B	To increase the SWR bandwidth
C	To cancel capacitive reactance
D	To lower the Q

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Dielectric constant
B	Characteristic impedance
C	Velocity factor
D	Reflection coefficient

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

Select	Answer
A	Standing wave ratio
B	Surge impedance
C	Velocity factor
D	Characteristic impedance

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Standing wave ratio circles
B	Radiation-pattern circles
C	Coaxial-length circles
D	Antenna-length circles

49. - E9H11

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

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

50. - E0A11

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

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

Figure E5-2

Figure E7-3

Figure E7-4

Figure E9-1