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

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

3. - E1C09

Which of these ranges of frequencies is available for an automatically controlled repeater operating below 30 MHz?

Select	Answer
A	18.110 MHz - 18.168 MHz
B	29.500 MHz - 29.700 MHz
C	10.100 MHz - 10.150 MHz
D	24.940 MHz - 24.990 MHz

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
B	Any amateur station on the surface of the Earth
C	An amateur station that transmits telemetry consisting of measurement of upper atmosphere
D	An amateur station that is not able to communicate using amateur satellites

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Return the application document to the examinee
B	Destroy the application form
C	Send the application form to the FCC and inform the FCC of the grade
D	Maintain the application form with the VEC's records

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must exhibit a gain of 0 dB or less over its full output range
B	It must produce full legal output when driven by not more than 5 watts of mean RF input power
C	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
D	It must be capable of external RF switching between its input and output networks

7. - E2A14

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

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

8. - E2B19

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

Select	Answer
A	They are not permitted above 54 MHz
B	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
C	None; they are allowed on all amateur frequencies
D	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

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A method of exchanging information during a contest QSO
B	A standard for submission of electronic contest logs
C	The rules of order for meetings between contest sponsors
D	The most common set of contest rules

10. - E2D08

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

Select	Answer
A	Connect
B	Acknowledgement
C	Unnumbered Information
D	Disconnect

11. - E2E06

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

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

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	2000 miles, if the Moon is at apogee
B	12,000 miles, if the Moon is visible by both stations
C	5000 miles, if the Moon is at perigee
D	500 miles, if the Moon is at perigee

13. - E3B06

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

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

14. - E3C15

What might a sudden rise in radio background noise indicate?

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

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
B	It divides a higher frequency signal so a low-frequency counter can display the input frequency
C	It amplifies low level signals for more accurate counting
D	It prevents oscillation in a low-frequency counter circuit

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1465.20 Hz
B	146.52 kHz
C	146.52 Hz
D	10 Hz

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

Select	Answer
A	RAM speed used for data storage
B	Anti-aliasing input filter bandwidth
C	CPU register width in bits
D	Analog-to-digital converter sample width in bits

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the signals from the transmitters are reflected in phase from airplanes passing overhead
B	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
C	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
D	When the signals from the transmitters are reflected out of phase from airplanes passing overhead

19. - E4E06

What is a major cause of atmospheric static?

Select	Answer
A	Meteor showers
B	Solar radio frequency emissions
C	Thunderstorms
D	Geomagnetic storms

20. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

Select	Answer
A	The current leads the voltage by 90 degrees
B	The voltage leads the current by 90 degrees
C	The voltage and current are in phase
D	The voltage and current are 180 degrees out of phase

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Voltage and current are 180 degrees out of phase
B	Current leads voltage by 90 degrees
C	Voltage leads current by 90 degrees
D	Voltage and current are in phase

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 5
B	Point 8
C	Point 3
D	Point 1

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Malleability
B	Permittivity
C	Permeability
D	Inductance

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	Any FET for which holes are the majority carriers
B	An FET that has no current flow between source and drain when no gate voltage is applied
C	An FET that exhibits a current flow between source and drain when no gate voltage is applied
D	Any FET without a channel

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Forward DC bias current
B	Reverse voltage larger than the RF signal
C	A sub-harmonic pump signal
D	Capacitance of an RF coupling capacitor

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
B	All of these choices are correct
C	Its simplicity results in much less expensive devices than standard CMOS
D	It is totally immune to electrostatic damage

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Permeability
B	Resistance
C	Thermal impedance
D	Reactivity

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	TO-220
B	Surface mount
C	Radial lead
D	Axial lead

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It increases
B	It decreases
C	It becomes unstable
D	It stays the same

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It produces ten output pulses for every input pulse
B	It produces one output pulse for every ten input pulses
C	It decodes a decimal number for display on a seven segment LED display
D	It adds two decimal numbers together

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they maintain the sidebands, thus causing multiple duplicate signals
B	Because they are relatively far in frequency from the desired signal
C	Because they invert the sidebands causing distortion
D	Because they are relatively close in frequency to the desired signal

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

Select	Answer
A	Meteor scatter
B	Video
C	Single-Sideband voice
D	Digital

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To improve output voltage regulation
B	To cut down on waste heat generated by the power supply
C	To boost the amount of output current
D	To balance the low-voltage filament windings

34. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the oscillator
B	A reactance modulator on the final amplifier
C	A reactance modulator on the oscillator
D	A balanced modulator on the audio amplifier

35. - E7F07

What function can a Fast Fourier Transform perform?

Select	Answer
A	Converting digital signals from the time domain to the frequency domain
B	Converting digital signals to analog form
C	Converting 8-bit data to 16 bit data
D	Converting analog signals to digital form

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	94
B	47
C	24
D	0.21

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

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Level shifting
B	Harmonic regeneration
C	Phase reversal
D	Sequential sampling

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	High speed digital modes
B	OFDM signals are not allowed on amateur bands
C	EME
D	Extremely low-power contacts

40. - E8C10

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

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

41. - E8D06

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

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

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Transmission-line resistance plus radiation resistance
B	Radiation resistance plus transmission resistance
C	Radiation resistance plus space impedance
D	Radiation resistance plus ohmic resistance

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Radiation resistance
B	Azimuth
C	Elevation
D	Polarization

44. - E9C10

Which of the following describes a Zepp antenna?

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

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

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
B	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna
C	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable
D	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	20 meters
B	2.3 meters
C	0.2 meters
D	3.5 meters

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 current axis
D	The resistance axis

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It modifies the pattern of a DF antenna array to provide a null in one direction
B	It allows DF antennas to receive signals at different vertical angles
C	It provides diversity reception that cancels multipath signals
D	It increases the sensitivity of a DF antenna array

50. - E0A10

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

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

Figure E5-2

Figure E7-4

Figure E9-2

Figure E9-3