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	1.5 kHz
B	170 Hz
C	2.8 kHz
D	60 Hz

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Florida surrounding Cape Canaveral
B	An area surrounding the National Radio Astronomy Observatory
C	An area in Puerto Rico surrounding the Arecibo Radio Telescope
D	An area in New Mexico surrounding the White Sands Test Area

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	A station operating with its output power controlled automatically
D	Remotely controlling a station's antenna pattern through a directional control link

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	33 cm and 13 cm
B	70 cm only
C	70 cm and 13 cm
D	70 cm and 33 cm

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

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By calculations using the Keplerian elements for the specified satellite
B	By adding the mean anomaly to the orbital inclination
C	By subtracting the mean anomaly from the orbital inclination
D	By means of the Doppler data for the specified satellite

8. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To lock the color burst oscillator in color SSTV images
B	To identify the SSTV mode being used
C	To provide vertical synchronization
D	To identify the call sign of the station transmitting

9. - E2C09

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

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

10. - E2D11

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

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

11. - E2E07

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

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

12. - E3A13

Which emission mode is best for aurora propagation?

Select	Answer
A	SSB
B	RTTY
C	FM
D	CW

13. - E3B05

Which amateur bands typically support long-path propagation?

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

14. - E3C07

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

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

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Bit error rate tester
B	Network analyzer
C	Logic analyzer
D	Modulation monitor

16. - E4B11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Select	Answer
A	Connect the antenna feed line directly to the analyzer's connector
B	Loosely couple the antenna and a dummy load to the analyzer
C	Loosely couple the analyzer near the antenna base
D	Connect the analyzer via a high-impedance transformer to the antenna

17. - E4C12

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?

Select	Answer
A	Filter ringing
B	Thermal-noise distortion
C	Output-offset overshoot
D	Undesired signals may be heard

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To store often-used frequencies
B	To allow selection of the optimum RF amplifier device
C	To increase rejection of unwanted signals
D	To provide a range of AGC time constants

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By observing the AC power line voltage with a spectrum analyzer
B	By checking the power line voltage with a time domain reflectometer
C	By turning off the AC power line main circuit breaker and listening on a battery operated radio
D	By observing the AC power line waveform with an oscilloscope

20. - E5A13

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

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

21. - E5B06

What is susceptance?

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

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	The sum of the reactive and resistive components
B	The difference between the resistive and reactive components
C	Resistive component
D	Reactive component

23. - E5D01

What is the result of skin effect?

Select	Answer
A	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface
B	Thermal effects on the surface of the conductor increase the impedance
C	Thermal effects on the surface of the conductor decrease the impedance
D	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Alpha rejection frequency
B	Alpha cutoff frequency
C	Beta cutoff frequency
D	Corner frequency

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Tunnel diode
B	Varactor diode
C	Zener diode
D	Silicon-controlled rectifier

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	More efficient arithmetic operations
B	Ability to connect many device outputs to a common bus
C	High speed operation
D	Low power consumption

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
C	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
D	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance

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	Axial lead
D	Radial lead

29. - E6F01

What is photoconductivity?

Select	Answer
A	The decreased conductivity of an illuminated semiconductor
B	The conversion of photon energy to electromotive energy
C	The increased conductivity of an illuminated semiconductor
D	The conversion of electromotive energy to photon energy

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	A flip-flop
B	An XOR gate
C	An OR gate
D	A multiplexer

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

Select	Answer
A	Class AB
B	Push-push
C	Class C
D	Push-pull

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Omega
B	Pi-L
C	Cascode
D	Pi

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 regulator
B	A series current source
C	A shunt current source
D	A series regulator

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. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	Select the point at which baseband signals are generated
B	To reduce excess signal pressure levels
C	Provide access for debugging software
D	Provide incremental signal delays for filter algorithms

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
B	The potential between the amplifier input terminals of the op-amp in an open loop condition
C	The output voltage of the op-amp minus its input voltage
D	The differential input voltage needed to bring the open loop output voltage to zero

37. - E7H11

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

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

38. - E8A05

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

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

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the audio modulating frequency to the center carrier frequency
B	The ratio of the highest audio modulating frequency to the average audio modulating frequency
C	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
D	The ratio of the carrier center frequency to the audio modulating frequency

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 number of characters carried per second by the station-to-station link
C	The rate at which the waveform of a transmitted signal changes to convey information
D	The number of control characters in a message packet

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

42. - E9A08

What is meant by antenna bandwidth?

Select	Answer
A	The angle formed between two imaginary lines drawn through the element ends
B	Antenna length divided by the number of elements
C	The angle between the half-power radiation points
D	The frequency range over which an antenna satisfies a performance requirement

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	The E-field and H-field patterns may reverse
B	Feed point impedance may become negative
C	The gain may change depending on frequency
D	Element spacing limits could be exceeded

44. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The front-to-back ratio decreases
B	The lobes align more in the direction of the wire
C	The lobes become more perpendicular to the wire
D	The vertical angle increases

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

Select	Answer
A	It radiates the harmonics and fundamental equally well
B	It must be neutralized
C	It is too sharply directional at lower frequencies
D	It might radiate harmonics

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The omega matching system
B	The delta matching system
C	The stub matching system
D	The gamma matching system

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

48. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Voltage lines and current chords
B	Resistance lines and reactance chords
C	Voltage circles and current arcs
D	Resistance circles and reactance arcs

49. - E9H04

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

Select	Answer
A	It automatically cancels ignition noise in mobile installations
B	It is electro statically balanced against ground, giving better nulls
C	It allows stations to communicate without giving away their position
D	It eliminates tracking errors caused by strong out-of-band signals

50. - E0A08

What does SAR measure?

Select	Answer
A	Synthetic Aperture Ratio of the human body
B	The rate of RF energy reflected from stationary terrain
C	The rate at which RF energy is absorbed by the body
D	Signal Amplification Rating