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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the lowest frequency of the channel
B	At the highest frequency of the channel
C	At the center frequency of the channel
D	On any frequency where the signal's sidebands are within the channel

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	No special rules apply if your antenna structure will be less than 300 feet in height
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	You must file an Environmental Impact Statement with the EPA before construction begins

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	The U.S. embassy must approve of your operation
B	You must append "/CEPT" to your call sign
C	You must bring a copy of FCC Public Notice DA 11-221
D	You must identify in the official language of the country in which you are operating

4. - E1D01

What is the definition of the term telemetry?

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

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The VE session manager
B	Each administering VE
C	The VEC coordinating the session
D	The FCC

6. - E1F10

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

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

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 north to south
D	From east to west

8. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	A special notch filter to remove synchronization pulses
B	A special IF converter
C	A special front end limiter
D	No other hardware is needed

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
B	The ARRL section of the remote station
C	/R# where # is the district of the remote station
D	No additional indicator is required

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	It supplies signals to guide the antenna to track the Moon
B	All of these choices are correct
C	It controls the receiver to track Doppler shift
D	It can decode signals many dB below the noise floor using FEC

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	RTTY
B	MFSK
C	Winlink
D	PSK31

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is full
B	When the Moon is at perigee
C	When the MUF is above 30 MHz
D	When the Moon is at apogee

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Any time
B	Around sunset
C	Around sunrise
D	Early evening

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	Westward
C	Eastward
D	Northward

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

Select	Answer
A	False signals are displayed
B	All signals will have a DC offset
C	False triggering occurs
D	Calibration of the vertical scale is no longer valid

16. - E4B15

Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?

Select	Answer
A	The inductance to capacitance ratio
B	The frequency shift
C	The resonant frequency of the circuit
D	The bandwidth of the circuit's frequency response

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Cross-modulation interference
B	Capture effect
C	Frequency discrimination
D	Desensitization

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

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	A malfunctioning illuminated advertising display
B	A defective doorbell or doorbell transformer inside a nearby residence
C	Arcing contacts in a thermostatically controlled device
D	All of these choices are correct

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	31.4 kHz
B	15.7 kHz
C	436.6 kHz
D	218.3 kHz

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	G
B	Y
C	B
D	X

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Venn diagram
B	Near field diagram
C	Phasor diagram
D	Far field diagram

23. - E5D03

What is microstrip?

Select	Answer
A	Miniature coax used for low power applications
B	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
C	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
D	Lightweight transmission line made of common zip cord

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Alpha cutoff frequency
B	Corner frequency
C	Beta cutoff frequency
D	Alpha rejection frequency

25. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Excessive inverse voltage
B	Charge carrier depletion
C	Excessive junction temperature
D	Insufficient forward voltage

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	Input signals are stronger
B	The input switching threshold is about two times the power supply voltage
C	Larger bypass capacitors are used in CMOS circuit design
D	The input switching threshold is about one-half the power supply voltage

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	Feedback capacitor
B	Clipper capacitor
C	Snubber capacitor
D	Trimmer capacitor

28. - E6E10

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

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

29. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	0.5 V
B	12 V
C	1.5 V
D	0.1 V

30. - E7A10

What is a truth table?

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

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A matched load resistor to prevent damage by switching transients
B	A low-pass filter to remove switching signal components
C	A temperature compensating load resistor to improve linearity
D	A high-pass filter to compensate for low gain at low frequencies

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

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A series current source
B	A series regulator
C	A shunt regulator
D	A shunt current source

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The unmodulated bandwidth of the transmitted signal
B	The lowest frequency band that the transmitter or receiver covers
C	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
D	The frequency components present in the modulating signal

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At half the rate of the highest frequency component of the signal
B	At four times the rate of the highest frequency component of the signal
C	At twice the rate of the highest frequency component of the signal
D	At the same rate as the highest frequency component of the signal

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	As an audio filter in a receiver
B	For smoothing power supply output
C	As a low-pass filter used between a transmitter and a transmission line
D	As a high-pass filter used to block RFI at the input to receivers

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

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	8 multiplied by the gain of the input amplifier
B	256
C	8
D	256 divided by the gain of the input amplifier

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the highest audio modulating frequency to the average audio modulating frequency
B	The ratio of the carrier center frequency to the audio modulating frequency
C	The ratio of the audio modulating frequency to the center carrier frequency
D	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency

40. - E8C02

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

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

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Binary phase-shift keying
B	Direct sequence
C	Phase compandored spread spectrum
D	Frequency hopping

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(effective radiated power / transmitter output) x 100 percent
B	(radiation resistance / transmission resistance) x 100 per cent
C	(total resistance / radiation resistance) x 100 per cent
D	(radiation resistance / total resistance) x 100 per cent

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

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 broadside to the axis of the array
D	A Figure-8 end-fire along the axis of the array

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth increases
B	Gain is reduced
C	More common-mode current is present on the feed line
D	SWR bandwidth decreases

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	An SWR greater than 1:1
B	A dielectric constant greater than 1
C	An SWR less than 1:1
D	A reflection coefficient greater than 1

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	Very low impedance
C	Very high impedance
D	The same as the characteristic impedance of the line

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and voltage
B	Reactance and voltage
C	Resistance and reactance
D	Voltage and impedance

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	They must be erected at least 1/2 wavelength above the ground to attain good directivity
B	Atmospheric noise is so high that gain over a dipole is not important
C	Low loss coax transmission line is essential for good performance
D	All of these choices are correct

50. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Select	Answer
A	Polymorphic silicon
B	Polyethylene
C	Polychlorinated Biphenyls
D	Polytetrafluroethylene