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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	No, the sideband will extend beyond the band edge
B	Yes, because the displayed frequency is within the 20 meter band
C	Yes, because you were not the station calling CQ
D	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz

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. - E1C01

What is a remotely controlled station?

Select	Answer
A	A station controlled by someone other than the licensee
B	A station operated away from its regular home location
C	A station controlled indirectly through a control link
D	A station operating under automatic control

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	All HF bands
B	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

Select	Answer
A	The exam proctor observes the applicants and reports any violations
B	Record the exam session on video tape for later review by the VE team
C	Have each applicant sign an affidavit stating that all session rules were followed
D	Use a real-time video link and the Internet to connect the exam session to the observing VEs

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
B	The transmission must not be used to obscure the meaning of any communication
C	All of these choices are correct
D	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions

7. - E2A01

What is the direction of an ascending 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. - E2B04

What is blanking in a video signal?

Select	Answer
A	Synchronization of the horizontal and vertical sync pulses
B	Transmitting a black and white test pattern
C	Turning off the scanning beam at the conclusion of a transmission
D	Turning off the scanning beam while it is traveling from right to left or from bottom to top

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Operators are permitted to make contacts even if they do not submit a log
B	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
C	Every contest requires a signal report in the exchange
D	Interference to other amateurs is unavoidable and therefore acceptable

10. - E2D11

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

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

11. - E2E12

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

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

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves that circle the Earth
B	Waves produced by a loop antenna
C	Waves with an electric field bent into a circular shape
D	Waves with a rotating electric field

13. - E3B10

What is the cause of gray-line propagation?

Select	Answer
A	In darkness, solar absorption drops greatly while atmospheric ionization remains steady
B	At twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high
C	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
D	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves

14. - E3C11

What does VOACAP software model?

Select	Answer
A	AC current and impedance
B	HF propagation
C	AC voltage and impedance
D	VHF radio propagation

15. - E4A05

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

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

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S21
B	S11
C	S12
D	S22

17. - E4C16

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

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

18. - E4D03

How can intermodulation interference between two repeaters occur?

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

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	The audio frequency bandwidth of the received signal might be compressed
B	Received audio in the speech range might have an echo effect
C	Nearby signals may appear to be excessively wide even if they meet emission standards
D	FM signals can no longer be demodulated

20. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	Minimum
B	L/R
C	R/L
D	Maximum

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	220 seconds
B	110 seconds
C	440 seconds
D	55 seconds

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	Omega
B	-jX
C	X
D	+jX

23. - E5D13

How much power is consumed in a circuit consisting of a 100 ohm resistor in series with a 100 ohm inductive reactance drawing 1 ampere?

Select	Answer
A	141.4 Watts
B	70.7 Watts
C	100 Watts
D	200 Watts

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to gate current
B	The change of collector current with respect to emitter current
C	The change of base current with respect to collector current
D	The change of collector current with respect to base current

25. - E6B11

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

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

26. - E6C09

What is a Programmable Logic Device (PLD)?

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

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	Trimmer capacitor
C	Snubber capacitor
D	Clipper capacitor

28. - E6E04

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

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

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of light to electrical energy
B	The conversion of voltage to current when exposed to light
C	The conversion of electrical energy to mechanical energy
D	The tendency of a battery to discharge when used outside

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	1
B	2
C	4
D	8

31. - E7B13

In Figure E7-2, what is the purpose of R?

Select	Answer
A	Collector load
B	Fixed bias
C	Voltage regulation
D	Emitter load

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

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	An SCR
B	A varactor diode
C	A Zener diode
D	A tunnel diode

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Discriminator
B	Product detector
C	Phase comparator
D	Phase detector

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Sample clock phase noise
B	Missing codes and jitter
C	Reference voltage level and sample width in bits
D	Data storage transfer rate

36. - E7G06

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

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

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Spurious signals at discrete frequencies
B	Digital conversion noise
C	Broadband noise
D	Nyquist limit noise

38. - E8A13

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

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

39. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	1.67
B	60
C	0.167
D	0.6

40. - E8C02

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

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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Excessive transmit audio levels
B	Bit errors in the modem
C	Ground loops
D	Excessive numbers of retries

42. - E9A09

How is antenna efficiency calculated?

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

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of segments, each having a distinct value of voltage across it
B	A wire is modeled as a series of points, each having a distinct location in space
C	A wire is modeled as a single sine-wave current generator
D	A wire is modeled as a series of segments, each having a uniform value of current

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	A dipole constructed from zip cord
D	An omni-directional antenna commonly used for satellite communications

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
B	An electrically short connection to a metal water pipe
C	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
D	A 50 ohm resistor connected to ground

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	Double-bazooka match
B	All of these choices are correct
C	Hairpin match
D	Gamma match

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	A capacitive reactance
C	An inductive reactance
D	The same as the input impedance to the final generator stage

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

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

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 eliminates tracking errors caused by strong out-of-band signals
D	It is electro statically balanced against ground, giving better nulls

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Lightning protection
B	Reduce RFI to telephones and home entertainment systems
C	Reduce received noise
D	Reduce RF current flow between pieces of equipment

Figure E7-2