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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	1 kHz above the lower band edge
B	The exact lower band edge
C	300 Hz above the lower band edge
D	3 kHz above the lower band edge

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
B	Only those club stations licensed to Amateur Extra class operators
C	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
D	Any FCC-licensed amateur station except a Technician class

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	Remotely controlling a station's antenna pattern through a directional control link
B	The use of devices and procedures for control so that the control operator does not have to be present at a control point
C	A station operating with its output power controlled automatically
D	The use of a control link between a control point and a locally controlled station

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of General, Advanced or Amateur Extra Class operators
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	Any amateur station, subject to the privileges of the class of operator license held by the control operator

5. - E1E08

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

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

6. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When neither the amateur nor his or her employer has a pecuniary interest in the communications
B	When the control operator is employed by the FCC or another government agency
C	When transmitting international third-party communications
D	When the total money involved does not exceed $25

7. - E2A13

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

Select	Answer
A	Geostationary
B	LEO
C	Geomagnetic
D	HEO

8. - E2B12

How are analog SSTV images typically transmitted on the HF bands?

Select	Answer
A	Video is converted to equivalent ASCII representation
B	Varying tone frequencies representing the video are transmitted using PSK
C	Varying tone frequencies representing the video are transmitted using single sideband
D	Video is converted to equivalent Baudot representation

9. - E2C05

What is the function of a DX QSL Manager?

Select	Answer
A	To allocate frequencies for DXpeditions
B	To relay calls to and from a DX station
C	To run a net to allow many stations to contact a rare DX station
D	To handle the receiving and sending of confirmation cards for a DX station

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Radio direction finding spectrum analysis
B	Latitude and longitude
C	Time and frequency
D	Polar coordinates

11. - E2E12

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

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

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	10 MHz - 14 MHz
B	1.8 MHz - 1.9 MHz
C	220 MHz - 450 MHz
D	28 MHz - 148 MHz

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	80 meters
B	6 meters
C	10 meters
D	20 meters

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	50 percent greater
B	Twice as great
C	Four times as great
D	10 percent greater

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Bit error rate tester
B	Modulation monitor
C	Network analyzer
D	Logic analyzer

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	Relative quality of the data
B	The relative time between measurements
C	Frequency order of the measurements
D	The port or ports at which measurements are made

17. - E4C05

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

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

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	Third-order intermodulation produces three products for every input signal within the band of interest
B	The third-order intercept is much higher than other orders
C	Third-order products are an indication of poor image rejection
D	The third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	Harmonics of the AC power line frequency
B	A differential-mode signal at the AC power line frequency
C	An electrical-sparking signal
D	A common-mode signal at the frequency of the radio transmitter

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	218.3 kHz
B	31.4 kHz
C	436.6 kHz
D	15.7 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	110 seconds
B	220 seconds
C	440 seconds
D	55 seconds

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 5
B	Point 6
C	Point 2
D	Point 4

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In a direction determined by the left-hand rule
B	In a direction opposite to the current
C	In the same direction as the current
D	In all directions; omni-directional

24. - E6A04

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

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

25. - E6B10

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

Select	Answer
A	6
B	1
C	5
D	7

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To prevent input noise from causing unstable output signals
B	To increase the sensitivity
C	To cause the output to change states continually
D	To allow the comparator to be used with AC input signal

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
C	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
D	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Nearly infinite gain, very high input impedance, and very low output impedance
B	Plate current that is controlled by a control grid
C	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
D	The ability to retrieve information from a single signal even in the presence of other strong signals

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	An ordinary metal
B	A liquid semiconductor
C	A heavy metal
D	A crystalline semiconductor

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	J-K flip-flop
B	T flip-flop
C	Monostable multivibrator
D	Astable multivibrator

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	Select transistors with high beta
B	All of these choices are correct
C	Use a resistor in series with the emitter
D	Neutralization

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	An all-pass filter
B	A band-pass filter
C	A Pi-network filter
D	A notch filter

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 drops when the input voltage is varied over its specified range
C	Minimum input voltage for rated power dissipation
D	Maximum amount that the output voltage may decrease at rated load

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. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Removing unnecessary significant digits
B	Attenuating the signal
C	Converting data to binary code decimal form
D	Reducing the effective sample rate by removing samples

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 high-pass filter used to block RFI at the input to receivers
C	As a low-pass filter used between a transmitter and a transmission line
D	As an audio filter in a receiver

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a reference oscillator and the output waveform
B	The synthesizer frequency limits and frequency values stored in the radio memories
C	The amplitude values that represent a sine-wave output
D	The phase relationship between a voltage-controlled oscillator and the output waveform

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

Select	Answer
A	By using an absorption wave meter
B	By using a grid dip meter
C	By measuring the voltage with a D'Arsonval meter
D	By measuring the heating effect in a known resistor

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 digital combiner, which then pulse position modulates the transmitter
D	Two or more information streams are merged into a baseband, which then 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	Special polynomial codes provide automatic correction
D	If errors are detected, a retransmission is requested

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	Strong ALC action
B	Harmonics on higher bands
C	High reflected power
D	Rapid signal fading

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

Select	Answer
A	To calculate the front-to-back ratio of the antenna
B	To match impedances in order to minimize standing wave ratio on the transmission line
C	To calculate the front-to-side ratio of the antenna
D	To measure the near-field radiation density from a transmitting antenna

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. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

Select	Answer
A	Omni-directional
B	Cardioid
C	A Figure-8 end-fire along the axis of the array
D	A Figure-8 broadside to the axis of the array

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain does not change
B	Gain is multiplied by 0.707
C	Gain increases by 6 dB
D	Gain increases by 3 dB

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. - E9F11

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

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

48. - E9G08

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

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

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A small coil of wire tightly wound around a toroidal ferrite core
B	A vertical antenna coupled to a feed line through an inductive loop of wire
C	A large circularly polarized antenna
D	One or more turns of wire wound in the shape of a large open coil

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	Localized heating of the body from RF exposure in excess of the MPE limits
C	Hearing loss caused by high voltage corona discharge
D	Ingestion of ozone gas from the cooling system

Figure E5-2

Figure E6-3