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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Discontinue forwarding the communication as soon as you become aware of it
B	Notify the originating station that the communication does not comply with FCC rules
C	Discontinue forwarding all messages
D	Notify the nearest FCC Field Engineer's office

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	2.0
B	1.0
C	0.5
D	3.0

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	The use of a control link between a control point and a locally controlled station
B	The use of devices and procedures for control so that the control operator does not have to be present at a control point
C	Remotely controlling a station's antenna pattern through a directional control link
D	A station operating with its output power controlled automatically

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	6 meters, 2 meters, and 1.25 meters
B	2 meters and 1.25 meters
C	6 meters and 2 meters
D	2 meters

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	No expenses are authorized for reimbursement
B	Preparing, processing, administering and coordinating an examination for an amateur radio license
C	Teaching an amateur operator license examination preparation course
D	Providing amateur operator license examination preparation training materials

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 222 MHz
B	Only on amateur frequencies above 50 MHz
C	Only on amateur frequencies above 144 MHz
D	Only on amateur frequencies above 420 MHz

7. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

Select	Answer
A	FM and CW
B	PSK and Packet
C	All of these choices are correct
D	SSB and SSTV

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	20 KHz
B	3 KHz
C	15 KHz
D	10 KHz

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send only the last two letters of your call sign until you make contact
B	Send the call sign of the DX station three times, the words "this is", then your call sign three times
C	Send your full call sign once or twice
D	Send your full call sign and grid square

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	FSK441
B	APRS
C	WSPR
D	Hellschreiber

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	550 Hz
B	31 Hz
C	2.16 kHz
D	316 Hz

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	The waves are reflected by the ionosphere and return to their source
B	Changing electric and magnetic fields propagate the energy
C	The energy propagates through a medium with a high refractive index
D	Electric and magnetic fields become aligned as they travel

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	160 meters to 40 meters
B	6 meters to 2 meters
C	30 meters to 10 meters
D	160 meters to 10 meters

14. - E3C07

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

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

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
B	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
C	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	Relative quality of the data
B	The relative time between measurements
C	Frequency order of the measurements
D	The port or ports at which measurements are made

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio of atmospheric noise to phase noise
B	The ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network
C	The ratio of thermal noise to atmospheric noise
D	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	The third-order intercept is much higher than other orders
B	Third-order products are an indication of poor image rejection
C	Third-order intermodulation produces three products for every input signal within the band of interest
D	The third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Common mode currents on the shield and conductors
B	Low inductance ground connections at both ends of the shield
C	Tying all ground connections to a common point resulting in differential mode currents in the shield
D	Use of braided shielding material

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Parasitic effects are minimized
B	Fewer components are needed for the same performance
C	Internal voltages and circulating currents increase
D	Phase shift can become uncontrolled

21. - E5B12

What is admittance?

Select	Answer
A	The term for the gain of a field effect transistor
B	The unit used for Q factor
C	The inverse of impedance
D	The turns ratio of a transformer

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 1
B	Point 5
C	Point 3
D	Point 8

23. - E5D14

What is reactive power?

Select	Answer
A	Power consumed in wire resistance in an inductor
B	Power lost because of capacitor leakage
C	Wattless, nonproductive power
D	Power consumed in circuit Q

24. - E6A05

What is the alpha of a bipolar junction transistor?

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

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	6
B	5
C	7
D	1

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor that insures that an oscillator frequency does not drive lower over time
B	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
C	A resistor connected to an op-amp output that only functions when the logic output is false
D	A resistor in a keying circuit used to reduce key clicks

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	Clipper capacitor
C	Trimmer capacitor
D	Snubber capacitor

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Silicon
B	Silicon dioxide
C	Gallium nitride
D	Silicon nitride

29. - E6F06

Which of these materials is affected the most by photoconductivity?

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

30. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic "0" at its output if some but not all inputs are logic "1"
B	It produces logic "0" at its output only when all inputs are logic "0"
C	It produces logic "0" at its output only when all inputs are logic "1"
D	It produces logic "1" at its output only when all inputs are logic "1"

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	Linear amplifiers have high gain resulting in higher harmonic content
B	Switching amplifiers use push-pull circuits
C	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
D	Switching amplifiers operate at higher voltages

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
B	A variable bandwidth crystal lattice filter
C	An automatic notch filter
D	A special filter that emphasizes image responses

33. - E7D06

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

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

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A pre-emphasis network
B	A heterodyne suppressor
C	An audio prescaler
D	A de-emphasis network

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

Select	Answer
A	It removes low frequency signal components to eliminate the need for DC restoration
B	It peaks the response of the decimator, improving bandwidth
C	It removes high-frequency signal components which would otherwise be reproduced as lower frequency components
D	It notches out the sampling frequency to avoid sampling errors

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	0.23 volts
C	-2.3 volts
D	-0.23 volts

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a quartz crystal
B	Through a neutralizing capacitor
C	Through a tapped coil
D	Through link coupling

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

Select	Answer
A	By using an absorption wave meter
B	By using a grid dip meter
C	By measuring the heating effect in a known resistor
D	By measuring the voltage with a D'Arsonval meter

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A digital mode for narrow band, slow speed transmissions
B	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
C	A bandwidth compression technique using Fourier transforms
D	A frequency modulation technique which uses non-harmonically related frequencies

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	Special polynomial codes provide automatic correction
B	If errors are detected, a retransmission is requested
C	If errors are detected, redundant data is substituted
D	Special binary codes provide automatic correction

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	The signal can overpower interfering signals
B	Faster transmission rate
C	Foreign language characters can be sent
D	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth

42. - E9A18

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Effective radiated power
B	Apparent power
C	Power factor
D	Half-power bandwidth

43. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below the guideline of 10 segments per half-wavelength?

Select	Answer
A	The resulting design will favor radiation of harmonic energy
B	The computed feed point impedance may be incorrect
C	Ground conductivity will not be accurately modeled
D	The antenna will become mechanically unstable

44. - E9C12

Which of the following describes an extended double Zepp antenna?

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

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

46. - E9E13

What is a use for a Wilkinson divider?

Select	Answer
A	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
B	It is used to feed low-impedance loads from a high-impedance source
C	It is used to feed high-impedance antennas from a low-impedance source
D	It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedance

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	15 meters
B	10 meters
C	71 meters
D	20 meters

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Azimuth angle radiation pattern chart
B	Free space radiation directivity chart
C	Elevation angle radiation pattern chart
D	Smith chart

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	One or more turns of wire wound in the shape of a large open coil
B	A large circularly polarized antenna
C	A small coil of wire tightly wound around a toroidal ferrite core
D	A vertical antenna coupled to a feed line through an inductive loop of wire

50. - E0A10

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

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

Figure E5-2

Figure E6-3

Figure E7-3

Figure E7-4

Figure E9-3