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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

SelectAnswer
A1 kHz below the upper band edge
B3 kHz below the upper band edge
CThe exact upper band edge
D300 Hz below the upper band edge

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?

SelectAnswer
AYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
BYou must file an Environmental Impact Statement with the EPA before construction begins
CYou must obtain a construction permit from the airport zoning authority
DNo special rules apply if your antenna structure will be less than 300 feet in height

3. - E1C05

When may an automatically controlled station originate third party communications?

SelectAnswer
ANever
BWhen approved by the National Telecommunication and Information Administration
COnly when transmitting RTTY or data emissions
DWhen agreed upon by the sending or receiving station

4. - E1D02

What is the amateur satellite service?

SelectAnswer
AA radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
BA radio communications service using stations on Earth satellites for public service broadcast
CA radio communications service using amateur radio stations on satellites
DA spacecraft launching service for amateur-built satellites

5. - E1E14

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

SelectAnswer
ATeaching an amateur operator license examination preparation course
BProviding amateur operator license examination preparation training materials
CNo expenses are authorized for reimbursement
DPreparing, processing, administering and coordinating an examination for an amateur radio license

6. - E1F12

Who may be the control operator of an auxiliary station?

SelectAnswer
AAny licensed amateur operator
BOnly Technician, General, Advanced or Amateur Extra Class operators
COnly General, Advanced or Amateur Extra Class operators
DOnly Amateur Extra Class operators

7. - E2A03

What is the orbital period of an Earth satellite?

SelectAnswer
AThe time it takes for a satellite to complete one revolution around the Earth
BThe point of maximum height of a satellite's orbit
CThe point of minimum height of a satellite's orbit
DThe time it takes for a satellite to travel from perigee to apogee

8. - E2B11

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

SelectAnswer
ATo lock the color burst oscillator in color SSTV images
BTo provide vertical synchronization
CTo identify the call sign of the station transmitting
DTo identify the SSTV mode being used

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

SelectAnswer
AMultiple Frequency Shift Keying in the 10 GHz band
BSpread spectrum in the 2.4 GHz band
CStore and forward on the 440 MHz band
DFrequency division multiplex in the 24 GHz band

10. - E2D08

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

SelectAnswer
AAcknowledgement
BUnnumbered Information
CDisconnect
DConnect

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

SelectAnswer
AMFSK16
B300-baud packet
CPSK31
D170 Hz shift, 45 baud RTTY

12. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

SelectAnswer
A500 miles, if the Moon is at perigee
B2000 miles, if the Moon is at apogee
C5000 miles, if the Moon is at perigee
D12,000 miles, if the Moon is visible by both stations

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

SelectAnswer
AEarly evening
BAround sunset
CAround sunrise
DAny time

14. - E3C07

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

SelectAnswer
AClass B
BClass X
CClass A
DClass 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?

SelectAnswer
AThe same as the sample rate
BIt depends on how the data is stored internally
COne-tenth the sample rate
DOne-half the sample rate

16. - E4B15

Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?

SelectAnswer
AThe frequency shift
BThe inductance to capacitance ratio
CThe bandwidth of the circuit's frequency response
DThe resonant frequency of the circuit

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

SelectAnswer
A-174 dBm
B-164 dBm
C-155 dBm
D-148 dBm

18. - E4D03

How can intermodulation interference between two repeaters occur?

SelectAnswer
AWhen the signals from the transmitters are reflected out of phase from airplanes passing overhead
BWhen the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
CWhen the signals from the transmitters are reflected in phase from airplanes passing overhead
DWhen the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters

19. - E4E09

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

SelectAnswer
AFM signals can no longer be demodulated
BNearby signals may appear to be excessively wide even if they meet emission standards
CReceived audio in the speech range might have an echo effect
DThe audio frequency bandwidth of the received signal might be compressed

20. - E5A07

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

SelectAnswer
AMinimum
BL/R
CR/L
DMaximum

21. - E5B12

What is admittance?

SelectAnswer
AThe unit used for Q factor
BThe inverse of impedance
CThe term for the gain of a field effect transistor
DThe turns ratio of a transformer

22. - E5C10

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

SelectAnswer
AThe difference between the resistive and reactive components
BThe sum of the reactive and resistive components
CResistive component
DReactive component

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

SelectAnswer
A1600 watts
B600 watts
C200 watts
D1000 watts

24. - E6A13

What do the initials CMOS stand for?

SelectAnswer
ACommon Mode Oscillating System
BComplementary Metal-Oxide Semiconductor
CCommon Mode Organic Silicon
DComplementary Mica-Oxide Silicon

25. - E6B12

What is one common use for PIN diodes?

SelectAnswer
AAs an RF switch
BAs a constant voltage source
CAs a high voltage rectifier
DAs a constant current source

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

SelectAnswer
A1
B4
C3
D2

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

SelectAnswer
AElectrolytic capacitors
BSteel-core toroids
CFerrite beads
DButterworth filters

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

SelectAnswer
ATo provide a low-pass frequency response
BEnhanced sensitivity to light
CBetter dissipation of heat
DHigh-voltage insulating ability

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

SelectAnswer
AElectrons
BProtons
CPhotons
DHoles

30. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
APositive Logic
BNegative logic
CReverse Logic
DAssertive Logic

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

SelectAnswer
AAll of these choices are correct
BNeutralization
CUse a resistor in series with the emitter
DSelect transistors with high beta

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?

SelectAnswer
APi
BOmega
CCascode
DPi-L

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

SelectAnswer
AThe resistance of a control element is varied in direct proportion to the line voltage or load current
BIt is generally less efficient than a linear regulator
CIt gives a ramp voltage at its output
DThe controlled device's duty cycle is changed to produce a constant average output voltage

34. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy using a balanced modulator followed by a filter
BBy using a loop modulator followed by a mixer
CBy driving a product detector with a DSB signal
DBy using a reactance modulator followed by a mixer

35. - E7F11

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

SelectAnswer
AReference voltage level and sample width in bits
BData storage transfer rate
CMissing codes and jitter
DSample clock phase noise

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A0.07
B7
C14
D28

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough a neutralizing capacitor
BThrough link coupling
CThrough a quartz crystal
DThrough a tapped coil

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AVery high speed allows digitizing high frequencies
BImmunity to out of sequence coding reduces spurious responses
CVery low power consumption decreases frequency drift
DAll of these choices are correct

39. - E8B09

What is meant by deviation ratio?

SelectAnswer
AThe ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
BThe ratio of the carrier center frequency to the audio modulating frequency
CThe ratio of the audio modulating frequency to the center carrier frequency
DThe ratio of the highest audio modulating frequency to the average audio modulating frequency

40. - E8C01

How is Forward Error Correction implemented?

SelectAnswer
ABy transmitting a special algorithm to the receiving station along with the data characters
BBy transmitting extra data that may be used to detect and correct transmission errors
CBy varying the frequency shift of the transmitted signal according to a predefined algorithm
DBy the receiving station repeating each block of three data characters

41. - E8D01

Why are received spread spectrum signals resistant to interference?

SelectAnswer
ASignals not using the spread spectrum algorithm are suppressed in the receiver
BIf interference is detected by the receiver it will signal the transmitter to change frequencies
CThe high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
DThe receiver is always equipped with a digital blanker

42. - E9A18

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

SelectAnswer
APower factor
BHalf-power bandwidth
CApparent power
DEffective radiated power

43. - E9B05

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

SelectAnswer
ARadiation resistance
BAzimuth
CElevation
DPolarization

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

SelectAnswer
AThe low-angle radiation decreases
BBoth the high-angle and low-angle radiation decrease
CThe low-angle radiation increases
DThe high-angle radiation increases

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
AA cable with six or seven 18 gauge conductors in parallel
BA wide flat copper strap
CA single 12 gauge or 10 gauge stainless steel wire
DA resistive wire, such as spark plug wire

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

SelectAnswer
ATo provide a rejection notch that prevents the radiation of harmonics
BTo provide DC isolation between the feed line and the antenna
CTo cancel the inductive reactance of the matching network
DTo transform the antenna impedance to a higher value

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

SelectAnswer
AFoam dielectric has higher velocity factor
BFoam dielectric has lower safe operating voltage limits
CFoam dielectric has lower loss per unit of length
DAll of these choices are correct

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

SelectAnswer
AImpedance axis
BReactance axis
CPrime axis
DPolar axis

49. - E9H06

What is the triangulation method of direction finding?

SelectAnswer
AAntenna headings from several different receiving locations are used to locate the signal source
BA fixed receiving station plots three headings to the signal source
CA fixed receiving station uses three different antennas to plot the location of the signal source
DThe geometric angles of sky waves from the source are used to determine its position

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

SelectAnswer
AOnly commercial transmitters
BOnly the most powerful transmitter
CEach transmitter that produces 5 percent or more of its MPE limit at accessible locations
DEach transmitter operating with a duty-cycle greater than 50 percent

Figure E6-5

Figure E7-4

Figure E9-2

Figure E9-3