Anonymous User

Hamboozler

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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A05

What is the maximum power output permitted on the 60 meter band?

SelectAnswer
A50 watts PEP effective radiated power relative to a dipole
B50 watts PEP effective radiated power relative to an isotropic radiator
C100 watts PEP effective radiated power relative to the gain of a half-wave dipole
D100 watts PEP effective radiated power relative to an isotropic radiator

2. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AAn amateur station transmission made at random without the proper call sign identification
BAny transmitted signal that unintentionally interferes with another licensed radio station
CAn emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
DA signal transmitted to prevent its detection by any station other than the intended recipient

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

SelectAnswer
ACommunications incidental to the purpose of the amateur service and remarks of a personal nature
BBusiness-related messages for non-profit organizations
CAll of these choices are correct
DMessages intended for connection to users of the maritime satellite service

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

SelectAnswer
AAny amateur station so designated by the ITU
BAny amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
CAny amateur station designated by NASA
DAll of these choices are correct

5. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
AAll of these choices are correct
BRelatives of the VE as listed in the FCC rules
CFriends of the VE
DEmployees of the VE

6. - E1F07

When may an amateur station send a message to a business?

SelectAnswer
AWhen transmitting international third-party communications
BWhen neither the amateur nor his or her employer has a pecuniary interest in the communications
CWhen the control operator is employed by the FCC or another government agency
DWhen the total money involved does not exceed $25

7. - E2A12

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

SelectAnswer
ABy means of the Doppler data for the specified satellite
BBy calculations using the Keplerian elements for the specified satellite
CBy adding the mean anomaly to the orbital inclination
DBy subtracting the mean anomaly from the orbital inclination

8. - E2B16

Which is a video standard used by North American Fast Scan ATV stations?

SelectAnswer
ADRM
BPAL
CScottie
DNTSC

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

SelectAnswer
ASwitch to a higher frequency HF band
BSwitch to a lower frequency HF band
CWait 24 hours before attempting another communication on the band
DWait 90 minutes or so for the signal degradation to pass

10. - E2D08

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

SelectAnswer
AUnnumbered Information
BDisconnect
CAcknowledgement
DConnect

11. - E2E06

What is the most common data rate used for HF packet?

SelectAnswer
A1200 baud
B48 baud
C300 baud
D110 baud

12. - E3A12

What is the cause of auroral activity?

SelectAnswer
AThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
BThe interaction in the F2 layer between the solar wind and the Van Allen belt
CA low sunspot level combined with tropospheric ducting
DMeteor showers concentrated in the extreme northern and southern latitudes

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A2500 miles
B5000 miles
C7500 miles
D1000 miles

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

SelectAnswer
AIt decreases
BIt increases
CIt stays the same
DIt peaks at roughly 14 MHz

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

SelectAnswer
AIt divides a higher frequency signal so a low-frequency counter can display the input frequency
BIt multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
CIt amplifies low level signals for more accurate counting
DIt prevents oscillation in a low-frequency counter circuit

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

SelectAnswer
A125 watts
B25 watts
C75 watts
D100 watts

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

SelectAnswer
AOne-half the maximum sample rate
BThe reference voltage of the analog-to-digital converter
COne-half the maximum sampling buffer size
DThe maximum count value of the analog-to-digital converter

18. - E4D02

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

SelectAnswer
AOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
BCross-modulation of the desired signal and desensitization from strong adjacent signals
COscillator instability and severe audio distortion of all but the strongest received signals
DCross-modulation of the desired signal and insufficient audio power to operate the speaker

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

SelectAnswer
AAll of these choices are correct
BThe interfering signal may drift slowly across the HF spectrum
CThe interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
DThe interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

SelectAnswer
A31.4 kHz
B218.3 kHz
C436.6 kHz
D15.7 kHz

21. - E5B05

What happens to the magnitude of a reactance when it is converted to a susceptance?

SelectAnswer
AThe magnitude of the susceptance is the reciprocal of the magnitude of the reactance
BIt is unchanged
CThe sign is reversed
DIt is shifted by 90 degrees

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
BReactive component
CThe sum of the reactive and resistive components
DResistive component

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

SelectAnswer
AIt is dissipated in the formation of inductive and capacitive fields
BIt is dissipated as heat in the circuit
CIt is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
DIt is dissipated as kinetic energy in the circuit

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?

SelectAnswer
AAlpha cutoff frequency
BBeta cutoff frequency
CAlpha rejection frequency
DCorner frequency

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

SelectAnswer
A4
B5
C2
D6

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

SelectAnswer
AToroidal cores confine most of the magnetic field within the core material
BToroidal cores make it easier to couple the magnetic energy into other components
CToroidal cores exhibit greater hysteresis
DToroidal cores have lower Q characteristics

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

SelectAnswer
APoint-to-point construction
BGround-plane construction
CMicrostrip construction
DWave-soldering construction

29. - E6F05

Which describes an optical shaft encoder?

SelectAnswer
AA device which detects rotation of a control by interrupting a light source with a patterned wheel
BA device for generating RTTY signals by means of a rotating light source
CA digital encryption device often used to encrypt spacecraft control signals
DA device which measures the strength of a beam of light using analog to digital conversion

30. - E7A04

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

SelectAnswer
A4
B1
C8
D2

31. - E7B06

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

SelectAnswer
APush-push
BPush-pull
CClass C
DClass AB

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

SelectAnswer
AVideo
BMeteor scatter
CDigital
DSingle-Sideband voice

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

SelectAnswer
ATo boost the amount of output current
BTo cut down on waste heat generated by the power supply
CTo improve output voltage regulation
DTo balance the low-voltage filament windings

34. - E7E11

Which type of detector is used for demodulating SSB signals?

SelectAnswer
APhase detector
BDiscriminator
CProduct detector
DPhase comparator

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

SelectAnswer
AFast Fourier Transform
BSignal conditioning
CQuadrature mixing
DDecimation

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt increases linearly with increasing frequency
BIt decreases linearly with increasing frequency
CIt does not vary with frequency
DIt decreases logarithmically with increasing frequency

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

SelectAnswer
AToroidal inductors
BWirewound resistors
CNP0 capacitors
DNon-inductive resistors

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

SelectAnswer
AA cosine wave
BA sine wave
CA sawtooth wave
DA square wave

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

SelectAnswer
AQuieting index
BFM compressibility
CPercentage of modulation
DModulation index

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

SelectAnswer
AIt has more resolution than simple binary
BIt increases security
CIt has more possible states than simple binary
DIt facilitates error detection

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

SelectAnswer
AHigh reflected power
BStrong ALC action
CHarmonics on higher bands
DRapid signal fading

42. - E9A18

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

SelectAnswer
AEffective radiated power
BPower factor
CHalf-power bandwidth
DApparent power

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

SelectAnswer
AThe total amount of radiation from the directional antenna is increased by the gain of the antenna
BThey are the same
CThe total amount of radiation from the directional antenna is stronger by its front-to-back ratio
DThe radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna

44. - E9C09

What is a G5RV antenna?

SelectAnswer
AA wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
BA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
CA phased array antenna consisting of multiple loops
DA multi-band trap antenna

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

SelectAnswer
ATo minimize the Q
BTo minimize losses
CTo swamp out harmonics
DTo maximize losses

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?

SelectAnswer
AAll of these choices are correct
BGamma match
CHairpin match
DDouble-bazooka match

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

SelectAnswer
A2.3 meters
B20 meters
C0.2 meters
D3.5 meters

48. - E9G08

What is the process of normalization with regard to a Smith chart?

SelectAnswer
AReassigning reactance values with regard to the resistance axis
BReassigning impedance values with regard to the prime center
CReassigning prime center with regard to the reactance axis
DReassigning resistance values with regard to the reactance axis

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

SelectAnswer
AIt has a bidirectional pattern
BIt is non-rotatable
CIt is practical for use only on VHF bands
DIt receives equally well in all directions

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

SelectAnswer
AAny ordinary smoke detector can be used
BOnly with a carbon monoxide detector
CBy the odor
DBy the yellowish appearance of the gas

Figure E6-5