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

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1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

Select	Answer
A	No, U.S. stations are not permitted to use phone emissions below 3.610 MHz
B	Yes, because the DX station initiated the contact
C	Yes, because the displayed frequency is within the 75 meter phone band segment
D	No, the sideband will extend beyond the edge of the phone band segment

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

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	A station operating with its output power controlled automatically
C	The use of a control link between a control point and a locally controlled station
D	The use of devices and procedures for control so that the control operator does not have to be present at a control point

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must cease all transmissions after 5 years
B	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
C	All of these choices are correct
D	The space station must be capable of changing its orbit whenever such a change is ordered by NASA

5. - E1E04

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

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

6. - E1F08

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

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

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. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

Select	Answer
A	3 kHz
B	2 MHz
C	600 Hz
D	6 MHz

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To improve operating efficiency by reducing interference
B	All of these choices are correct
C	To separate the calling stations from the DX station
D	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations

10. - E2D11

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

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

11. - E2E12

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

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

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	5000 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	500 miles, if the Moon is at perigee

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Propagation across the geomagnetic equator
B	Successive ionospheric reflections without an intermediate reflection from the ground
C	Propagation away from the great circle bearing between stations
D	Signals reflected back toward the transmitting station

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately 15 percent of the distance
B	By approximately 50 percent of the distance
C	By approximately twice the distance
D	By approximately four times the distance

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	Calibration of the vertical scale is no longer valid
D	False triggering occurs

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	0.1 MHz
B	1.4652 Hz
C	14.652 Hz
D	1.4652 kHz

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The meter display sensitivity
B	The minimum discernible signal
C	The maximum detectable spectrum
D	The multiplex distortion stability

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The difference in dB between the noise floor and the third order intercept point
B	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
C	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
D	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Broadband white noise
B	All of these choices are correct
C	Ignition noise
D	Power line noise

20. - E5A15

Which of the following can increase Q for inductors and capacitors?

Select	Answer
A	Lower self-resonant frequency
B	Higher self-resonant frequency
C	Lower losses
D	Lower reactance

21. - E5B03

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

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

22. - E5C16

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

Select	Answer
A	Point 8
B	Point 3
C	Point 1
D	Point 7

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	200 watts
B	1000 watts
C	1600 watts
D	600 watts

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	Insulated gate
B	P-type
C	Bipolar
D	N-type

25. - E6B08

Which of the following describes a type of semiconductor diode?

Select	Answer
A	Thermionic emission diode
B	CMOS-field effect
C	Metal-semiconductor junction
D	Electrolytic rectifier

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

Select	Answer
A	2
B	6
C	4
D	5

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Butterworth filters
B	Ferrite beads
C	Steel-core toroids
D	Electrolytic capacitors

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	SOT
B	Ball grid array
C	PLCC
D	DIP

29. - E6F07

What is a solid state relay?

Select	Answer
A	A passive delay line
B	A relay using transistors to drive the relay coil
C	A mechanical relay that latches in the on or off state each time it is pulsed
D	A device that uses semiconductors to implement the functions of an electromechanical relay

30. - E7A11

What type of logic defines "1" as a high voltage?

Select	Answer
A	Reverse Logic
B	Assertive Logic
C	Negative logic
D	Positive Logic

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Increased overall intelligibility
B	Signal inversion
C	Reduced intermodulation products
D	Signal distortion and excessive bandwidth

32. - E7C07

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

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

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

Select	Answer
A	It increases the current-handling capability of the regulator
B	It provides D1 with current
C	It provides a constant load for the voltage source
D	It provides negative feedback to improve regulation

34. - E7E03

How does an analog phase modulator function?

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

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

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	2.3 volts
B	-2.3 volts
C	-0.23 volts
D	0.23 volts

37. - E7H08

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

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

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	256 divided by the gain of the input amplifier
D	8

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Quieting index
B	FM compressibility
C	Modulation index
D	Percentage of modulation

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	9.6 kHz
B	4.8 kHz
C	5.76 kHz
D	15.36 kHz

41. - E8D06

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

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

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Yagi
B	Isotropic antenna
C	Quarter-wave vertical
D	Half-wave dipole

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	Antenna gain
B	Polar plots of the far field elevation and azimuth patterns
C	All of these choices are correct
D	SWR vs frequency charts

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	A dipole constructed from zip cord
B	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
C	An end fed dipole antenna
D	An omni-directional antenna commonly used for satellite communications

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 increases by 6 dB
C	Gain is multiplied by 0.707
D	Gain increases by 3 dB

46. - E9E07

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

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

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. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The reactance axis
B	The voltage axis
C	The resistance axis
D	The current axis

49. - E9H04

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

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

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

Select	Answer
A	Any ordinary smoke detector can be used
B	By the odor
C	By the yellowish appearance of the gas
D	Only with a carbon monoxide detector

Figure E5-2

Figure E6-5

Figure E7-3

Figure E7-4

Figure E9-3