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

2. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference
B	The amateur station must cease operation on all frequencies above 30 MHz
C	The amateur station must cease operation
D	The amateur station must cease operation on all frequencies below 30 MHz

3. - E1C07

What is meant by local control?

Select	Answer
A	Controlling a station through a local auxiliary link
B	Automatically manipulating local station controls
C	Direct manipulation of the transmitter by a control operator
D	Controlling a repeater using a portable handheld transceiver

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	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
C	All of these choices are correct
D	Any amateur station designated by NASA

5. - E1E04

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

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

6. - E1F08

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

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

7. - E2A14

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

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

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
B	None; they are allowed on all amateur frequencies
C	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
D	They are not permitted above 54 MHz

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 440 MHz transceiver with a 9600 baud modem
B	A standard wireless router running custom software
C	A 2 meter VHF transceiver with a 1200 baud modem
D	An optical cable connection between the USB ports of 2 separate computers

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Acknowledgement
B	Unnumbered Information
C	Connect
D	Disconnect

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	Selective fading has occurred
B	One of the signal filters is saturated
C	The mark and space signal have been inverted
D	The receiver has drifted 5 kHz from the desired receive frequency

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
B	A wave of alternating current, in the core of an electromagnet
C	A wave consisting of two electric fields at parallel right angles to each other
D	A wave consisting of two magnetic fields at right angles to each other

13. - E3B08

What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?

Select	Answer
A	Long-path
B	Transequatorial
C	Sporadic-E
D	Gray-line

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. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Manipulation of time base after trace capture
B	Storage of traces for future reference
C	Automatic amplitude and frequency numerical readout
D	All of these choices are correct

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	25 watts
B	125 watts
C	100 watts
D	75 watts

17. - E4C10

Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?

Select	Answer
A	300 Hz
B	2400 Hz
C	6000 Hz
D	100 Hz

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Cross-modulation of the desired signal and desensitization from strong adjacent signals
B	Oscillator instability and severe audio distortion of all but the strongest received signals
C	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
D	Cross-modulation of the desired signal and insufficient audio power to operate the speaker

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

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

20. - E5A02

What is resonance in an electrical circuit?

Select	Answer
A	The highest frequency that will pass current
B	The frequency at which the reactive impedance equals the resistive impedance
C	The frequency at which the capacitive reactance equals the inductive reactance
D	The lowest frequency that will pass current

21. - E5B06

What is susceptance?

Select	Answer
A	The magnetic impedance of a circuit
B	The inverse of reactance
C	The ratio of magnetic field to electric field
D	A measure of the efficiency of a transformer

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 2
B	Point 6
C	Point 4
D	Point 5

23. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

Select	Answer
A	80 watts
B	50 watts
C	2000 watts
D	400 watts

24. - E6A04

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

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

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	An algorithm for simulating logic functions during circuit design
B	Programmable equipment used for testing digital logic integrated circuits
C	A device to control industrial equipment
D	A programmable collection of logic gates and circuits in a single integrated circuit

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores have lower Q characteristics
B	Toroidal cores confine most of the magnetic field within the core material
C	Toroidal cores make it easier to couple the magnetic energy into other components
D	Toroidal cores exhibit greater hysteresis

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	450 ohms
B	10 ohms
C	300 ohms
D	50 ohms

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Electrons
B	Protons
C	Photons
D	Holes

30. - E7A11

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

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

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

Select	Answer
A	Exactly 180 degrees
B	More than 180 degrees but less than 360 degrees
C	Less than 180 degrees
D	The entire cycle

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 notch filter
B	It is a band-pass 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 shunt current source
B	A series current source
C	A shunt regulator
D	A series regulator

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	For compatibility with transmitters using phase modulation
B	To reduce impulse noise reception
C	For higher efficiency
D	To remove third-order distortion products

35. - E7F17

What do the letters I and Q in I/Q Modulation represent?

Select	Answer
A	Inactive and Quiescent
B	In-phase and Quadrature
C	Instantaneous and Quenched
D	Instantaneous and Quasi-stable

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

Select	Answer
A	Restrict gain but increase Q
B	Increase both gain and Q
C	Restrict Q but increase gain
D	Restrict both gain and Q

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A phase locked loop synthesizer
B	A diode-switching matrix synthesizer
C	A hybrid synthesizer
D	A direct digital synthesizer

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Numerical analysis
B	Fourier analysis
C	Differential analysis
D	Vector analysis

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. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It increases security
B	It has more resolution than simple binary
C	It has more possible states than simple binary
D	It facilitates error detection

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	Limits data speed
B	The generation of RF harmonics
C	The generation of key clicks
D	More difficult to copy

42. - E9A06

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

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

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

Select	Answer
A	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
B	Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference
C	Draw two imaginary lines through the ends of the elements and measure the angle between the lines
D	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna

44. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

Select	Answer
A	The main lobe takeoff angle decreases in the downhill direction
B	The horizontal beam width increases in the uphill direction
C	The main lobe takeoff angle increases in the downhill direction
D	The horizontal beam width decreases in the downhill direction

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance increases and the capacitive reactance increases
B	The radiation resistance decreases and the capacitive reactance decreases
C	The radiation resistance increases and the capacitive reactance decreases
D	The radiation resistance decreases and the capacitive reactance increases

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Connect a parallel-resonant LC network across the antenna feed terminals
B	Connect a series-resonant LC network across the antenna feed terminals
C	Use the universal stub matching technique
D	Use a 50 ohm 1:1 balun between the antenna and feed line

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	50 meters
B	24 meters
C	10 meters
D	6.9 meters

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Impedance along transmission lines
B	Radiation resistance
C	Radio propagation
D	Antenna radiation pattern

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing the number of wire turns in the loop and reducing the area of the loop structure
B	By increasing either the number of wire turns in the loop or the area of the loop structure or both
C	By reducing the permeability of the loop shield
D	By winding adjacent turns in opposing directions

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Zinc oxide
B	Beryllium Oxide
C	Mica
D	Uranium Hexafluoride

Figure E5-2