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	170 Hz
C	1.5 kHz
D	60 Hz

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 on all frequencies below 30 MHz
D	The amateur station must cease operation

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	When approved by the National Telecommunication and Information Administration
B	Never
C	When agreed upon by the sending or receiving station
D	Only when transmitting RTTY or data emissions

4. - E1D06

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

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

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	3
B	4
C	5
D	2

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	The equipment dealer assembled it from a kit
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
D	It was imported from a manufacturer in another country and was certificated by that country's government

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The time it takes for a satellite to complete one revolution around the Earth
B	The time it takes for a satellite to travel from perigee to apogee
C	The point of maximum height of a satellite's orbit
D	The point of minimum height of a satellite's orbit

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Specific tone frequencies
B	A two-tone signal
C	Elapsed time
D	Specific tone amplitudes

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	To separate the calling stations from the DX station
C	All of these choices are correct
D	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
B	All of these choices are correct
C	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
D	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	MFSK16
B	PSK31
C	300-baud packet
D	170 Hz shift, 45 baud RTTY

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	100 miles to 300 miles
B	1200 miles
C	2500 miles
D	10 miles to 50 miles

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	Gray-line
C	Transequatorial
D	Sporadic-E

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class B
B	Class X
C	Class A
D	Class M

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

Select	Answer
A	One-half the sample rate
B	It depends on how the data is stored internally
C	The same as the sample rate
D	One-tenth the sample rate

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1.4652 MHz
B	165.2 Hz
C	146.52 Hz
D	14.652 kHz

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

Select	Answer
A	14.755 MHz
B	15.210 MHz
C	14.445 MHz
D	13.845 MHz

18. - E4D02

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

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

19. - E4E01

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

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

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It is at a maximum
B	It is at a minimum
C	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
D	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

Select	Answer
A	76 degrees with the voltage leading the current
B	14 degrees with the voltage lagging the current
C	76 degrees with the voltage lagging the current
D	14 degrees with the voltage leading the current

22. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

Select	Answer
A	Polar coordinates
B	Maidenhead grid
C	Faraday grid
D	Elliptical coordinates

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	70.7 Watts
B	100 Watts
C	200 Watts
D	141.4 Watts

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	6
B	2
C	3
D	1

25. - E6B11

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

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

26. - E6C08

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

Select	Answer
A	4
B	1
C	3
D	2

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

Select	Answer
A	Ferrite toroids generally have better temperature stability
B	Ferrite toroids generally have lower initial permeability
C	Ferrite toroids are easier to use with surface mount technology
D	Ferrite toroids generally require fewer turns to produce a given inductance value

28. - E6E02

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

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

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	A crystalline semiconductor
B	An ordinary metal
C	A liquid semiconductor
D	A heavy metal

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic "0" at its output if all inputs are logic "1"
B	It only produces logic "0" at its output when all inputs are logic "1"
C	It produces logic "1" at its output if any or all inputs are logic "1"
D	It produces logic "1" at its output if all inputs are logic "0"

31. - E7B10

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

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

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

Select	Answer
A	A matching network in which all components are isolated from ground
B	A Pi-network with an additional series inductor on the output
C	A Phase Inverter Load network
D	A network with only three discrete parts

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To compensate for variations of the incoming line voltage
B	To allow the filter capacitors to charge gradually
C	To provide a dual-voltage output for reduced power applications
D	To allow for remote control of the power supply

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The unmodulated bandwidth of the transmitted signal
B	The lowest frequency band that the transmitter or receiver covers
C	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
D	The frequency components present in the modulating signal

35. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

Select	Answer
A	Sample width in bits
B	Sample rate
C	Sample clock phase noise
D	Processor latency

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A RF amplifier used in the UHF and microwave regions
B	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
C	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
D	A digital audio amplifier whose characteristics are determined by components external to the amplifier

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Negative feedback and balanced feedback
B	Colpitts and Hartley
C	Pierce and Zener
D	Armstrong and deForest

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	Fourier analysis
B	Numerical analysis
C	Differential analysis
D	Vector analysis

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	47
B	0.214
C	2.14
D	0.47

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. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Frequency hopping
B	Binary phase-shift keying
C	Phase compandored spread spectrum
D	Direct sequence

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	8.15 dB
B	3.85 dB
C	6.0 dB
D	2.79 dB

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	24 dB
B	3 dB
C	28 dB
D	15 dB

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A wideband vertical antenna constructed from precisely tapered aluminum tubing
B	An end fed folded dipole antenna
C	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
D	A portable antenna erected using two push support poles

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
B	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
C	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
D	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes

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 epsilon match
B	The delta match
C	The stub match
D	The gamma match

47. - E9F04

What is the typical velocity factor for a coaxial cable with solid polyethylene dielectric?

Select	Answer
A	0.66
B	2.70
C	0.10
D	0.30

48. - E9G01

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

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

49. - E9H04

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

Select	Answer
A	It eliminates tracking errors caused by strong out-of-band signals
B	It automatically cancels ignition noise in mobile installations
C	It allows stations to communicate without giving away their position
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	Reduce RF current flow between pieces of equipment
B	Reduce RFI to telephones and home entertainment systems
C	Lightning protection
D	Reduce received noise

Figure E6-2

Figure E6-5

Figure E7-1

Figure E9-2