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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	2.8 kHz
B	1.5 kHz
C	170 Hz
D	60 Hz

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	A letter of intent must be filed with the National Audubon Society
C	A proposal must be submitted to the National Park Service
D	An Environmental Assessment must be submitted to the FCC

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Messages intended for connection to users of the maritime satellite service
B	All of these choices are correct
C	Business-related messages for non-profit organizations
D	Communications incidental to the purpose of the amateur service and remarks of a personal nature

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
B	Any amateur station so designated by the ITU
C	Any amateur station designated by NASA
D	All of these choices are correct

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

Select	Answer
A	In FCC Part 97
B	In a question pool maintained by all the VECs
C	In the appropriate FCC Report and Order
D	In a question pool maintained by the FCC

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 for experimental amateur communications
D	To provide temporary operation while awaiting normal licensing

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Bandwidth compressed LORAN
B	Radar
C	Doppler shift of beacon signals
D	APRS

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

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Frequency division multiplex in the 24 GHz band
B	Store and forward on the 440 MHz band
C	Spread spectrum in the 2.4 GHz band
D	Multiple Frequency Shift Keying in the 10 GHz band

10. - E2D13

What type of modulation is used for JT65 contacts?

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

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	300 baud
B	110 baud
C	1200 baud
D	48 baud

12. - E3A07

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

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

13. - E3B14

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

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

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	Long-path propagation is occurring
B	A meteor ping
C	Increased transequatorial propagation likely
D	A solar flare has occurred

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and frequency
B	SWR and time
C	SWR and frequency
D	RF amplitude and time

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

Select	Answer
A	The transmitter is not properly neutralized
B	There is more power going into the antenna
C	There is an impedance mismatch between the antenna and feed line
D	There is possibly a short to ground in the feed line

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Distortion
B	Loss of sensitivity
C	Overload
D	Excess output level

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

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

20. - E5A16

What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?

Select	Answer
A	23.5 MHz
B	7.12 MHz
C	23.5 kHz
D	7.12 kHz

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

Select	Answer
A	It is unchanged
B	It is shifted by 90 degrees
C	The sign is reversed
D	The susceptance phase angle is the inverse of the reactance phase angle

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By X and R values
B	By Y and G values
C	By phase angle and amplitude
D	By real and imaginary parts

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	355 W
D	704 W

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free protons
B	Free neutrons
C	Free electrons
D	Holes

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C08

In Figure E6-5, what is the schematic symbol for a NAND gate?

Select	Answer
A	4
B	1
C	2
D	3

27. - E6D02

What is the equivalent circuit of a quartz crystal?

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

28. - E6E03

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

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

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
B	A frequency-determining unit for a transmitter or receiver
C	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency
D	A display that uses a glowing liquid to remain brightly lit in dim light

30. - E7A06

What is a characteristic of a monostable multivibrator?

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

31. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

Select	Answer
A	Feedback
B	Fixed bias
C	Load resistors
D	Self bias

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	An automatic notch filter
B	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
C	A special filter that emphasizes image responses
D	A variable bandwidth crystal lattice filter

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. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	An audio prescaler
B	A de-emphasis network
C	A pre-emphasis network
D	A heterodyne suppressor

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	4 bits
B	6 bits
C	10 bits
D	8 bits

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 an audio filter in a receiver
D	As a low-pass filter used between a transmitter and a transmission line

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a quartz crystal
B	Through a tapped coil
C	Through a neutralizing capacitor
D	Through link coupling

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Remove harmonics from the output caused by the discrete analog levels generated
B	All of these choices are correct
C	Improve accuracy by removing out of sequence codes from the input
D	Lower the input bandwidth to increase the effective resolution

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	1/3
B	3
C	2000
D	6000

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Gray code
C	Excess 3 code
D	Extended Binary Coded Decimal Interchange Code

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Reduce keying waveform rise and fall times
B	Low-pass filters at the transmitter output
C	Increase keying waveform rise and fall times
D	High-pass filters at the transmitter output

42. - E9A06

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

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

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	The gain may change depending on frequency
C	Element spacing limits could be exceeded
D	Feed point impedance may become negative

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It decreases the ground loss
B	It reflects the standing waves on the antenna elements back to the transmitter
C	It changes the radiation pattern from bidirectional to unidirectional
D	It changes the radiation pattern from horizontal to vertical polarization

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	It becomes flat
B	It is decreased
C	It is increased
D	No change occurs

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The gamma match
B	The epsilon match
C	The delta match
D	The stub match

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

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

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

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

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	Its overall length must not exceed 1/4 wavelength
B	It should be one or more wavelengths long
C	It should be configured as a four-sided loop
D	It must be mounted more than 1 wavelength above ground

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

Select	Answer
A	Use a calibrated antenna analyzer
B	All of the choices are correct
C	Use a hand calculator plus Smith-chart equations to calculate the fields
D	Use an antenna modeling program to calculate field strength at accessible locations

Figure E6-5

Figure E7-1

Figure E7-3