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

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	50 watts PEP effective radiated power relative to an isotropic radiator
B	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
C	100 watts PEP effective radiated power relative to an isotropic radiator
D	50 watts PEP effective radiated power relative to a dipole

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 may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
B	No special rules apply if your antenna structure will be less than 300 feet in height
C	You must obtain a construction permit from the airport zoning authority
D	You must file an Environmental Impact Statement with the EPA before construction begins

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

Select	Answer
A	Only beacon, repeater or space stations
B	Only earth stations, repeater stations or model craft
C	Only auxiliary, repeater or space stations
D	Only auxiliary, beacon or space stations

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	33 cm and 13 cm
B	70 cm only
C	70 cm and 13 cm
D	70 cm and 33 cm

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	A sentence of up to one year in prison
B	A fine of up to $1000 per occurrence
C	All of these choices are correct
D	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant

6. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications transmitted for hire or material compensation, except as otherwise provided in the rules
B	Communications that have a religious content
C	Communications that have a political content, except as allowed by the Fairness Doctrine
D	Communications in a language other than English

7. - E2A03

What is the orbital period of an Earth satellite?

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

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	15 KHz
B	10 KHz
C	20 KHz
D	3 KHz

9. - E2C08

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

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

10. - E2D10

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

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

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PSK31
B	PACTOR
C	RTTY
D	MT63

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	The jet stream
B	Temperature inversion
C	Wind shear
D	Dust devil

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between any two points located on the magnetic equator
B	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
C	Propagation between two stations at the same latitude
D	Propagation between two continents by way of ducts along the magnetic equator

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It peaks at roughly 14 MHz
B	It stays the same
C	It increases
D	It decreases

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 divides a higher frequency signal so a low-frequency counter can display the input frequency
C	It amplifies low level signals for more accurate counting
D	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S22
B	S11
C	S12
D	S21

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It reduces receiver sensitivity
B	It limits the receiver's ability to receive strong signals
C	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
D	It decreases receiver third-order intermodulation distortion dynamic range

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A Class C final amplifier
B	A properly terminated circulator at the output of the transmitter
C	A Class D final amplifier
D	A band-pass filter in the feed line between the transmitter and receiver

19. - E4E05

How can noise from an electric motor be suppressed?

Select	Answer
A	By installing a brute-force AC-line filter in series with the motor leads
B	By installing a bypass capacitor in series with the motor leads
C	By using a ground-fault current interrupter in the circuit used to power the motor
D	By installing a high pass filter in series with the motor's power leads

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	47.3 kHz
B	157.8 Hz
C	315.6 Hz
D	23.67 kHz

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	220 seconds
B	110 seconds
C	440 seconds
D	55 seconds

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 3
B	Point 8
C	Point 1
D	Point 5

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

Select	Answer
A	252 W
B	1.42 mW
C	704 W
D	355 W

24. - E6A06

What is the beta of a bipolar junction transistor?

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

25. - E6B10

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

Select	Answer
A	7
B	6
C	5
D	1

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

Select	Answer
A	The comparator changes its output state
B	The feedback loop becomes unstable
C	The IC input can be damaged
D	The comparator enters latch-up

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Permeability
B	Resistance
C	Reactivity
D	Thermal impedance

28. - E6E10

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

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

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The output RF power divided by the input DC power
B	The open-circuit voltage divided by the short-circuit current under full illumination
C	The relative fraction of light that is converted to current
D	The effective payback period

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic "0" at its output if all inputs are logic "1"
B	It produces logic "1" at its output if any or all inputs are logic "1"
C	It produces logic "1" at its output if all inputs are logic "0"
D	It only produces logic "0" at its output when all inputs are logic "1"

31. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	Approximately half-way between saturation and cutoff
B	At a point where the bias resistor equals the load resistor
C	At a point where the load line intersects the zero bias current curve
D	Where the load line intersects the voltage axis

32. - E7C05

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

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

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage divided by output current
B	Voltage difference from input to output multiplied by output current
C	Output voltage multiplied by output current
D	Input voltage multiplied by input current

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce PM signals
B	By varying the tuning of an amplifier tank circuit to produce AM signals
C	By varying the tuning of a microphone preamplifier to produce AM signals
D	By varying the tuning of an amplifier tank circuit to produce PM signals

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	An adaptive filter
B	A Hilbert-transform filter
C	An elliptical filter
D	A notch filter

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	28
B	7
C	0.07
D	14

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Wirewound resistors
B	NP0 capacitors
C	Toroidal inductors
D	Non-inductive resistors

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	Digital signals can be regenerated multiple times without error
C	All of these choices are correct
D	Digital signals always occupy a narrower bandwidth

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
B	Two or more signals are arranged to share discrete time slots of a data transmission
C	Two or more signals are quadrature modulated to increase bandwidth efficiency
D	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The rate at which the waveform of a transmitted signal changes to convey information
B	The number of characters carried per second by the station-to-station link
C	The duration of each bit in a message sent over the air
D	The number of control characters in a message packet

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	The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
C	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A05

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

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

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	The E-field and H-field patterns may reverse
B	Element spacing limits could be exceeded
C	Feed point impedance may become negative
D	The gain may change depending on frequency

44. - E9C04

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

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

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
B	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
C	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
D	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase

46. - E9E07

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

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

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	An inductive reactance
B	The same as the input impedance to the final generator stage
C	The same as the characteristic impedance of the line
D	A capacitive reactance

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

Select	Answer
A	In fractions of transmission line electrical wavelength
B	In fractions of transmission line electrical frequency
C	In fractions of antenna electrical wavelength
D	In fractions of antenna electrical frequency

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It is electro statically balanced against ground, giving better nulls
B	It eliminates tracking errors caused by strong out-of-band signals
C	It allows stations to communicate without giving away their position
D	It automatically cancels ignition noise in mobile installations

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Lightning protection
B	Reduce received noise
C	Reduce RF current flow between pieces of equipment
D	Reduce RFI to telephones and home entertainment systems

Figure E5-2

Figure E6-3

Figure E7-4