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. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

SelectAnswer
AYes, because the DX station initiated the contact
BNo, the sideband will extend beyond the edge of the phone band segment
CYes, because the displayed frequency is within the 75 meter phone band segment
DNo, U.S. stations are not permitted to use phone emissions below 3.610 MHz

2. - E1B01

Which of the following constitutes a spurious emission?

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

3. - E1C01

What is a remotely controlled station?

SelectAnswer
AA station controlled by someone other than the licensee
BA station controlled indirectly through a control link
CA station operated away from its regular home location
DA station operating under automatic control

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

SelectAnswer
AOnly those of General, Advanced or Amateur Extra Class operators
BOnly those of Amateur Extra Class operators
CAny amateur station, subject to the privileges of the class of operator license held by the control operator
DAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

SelectAnswer
AThey must collect and submit the documents to the coordinating VEC for grading
BThey must collect and send the documents to the NCVEC for grading
CThey must collect and send the documents to the FCC according to instructions
DThey must submit the application document to the coordinating VEC according to the coordinating VEC instructions

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

SelectAnswer
AFull privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
BAll privileges of the Extra Class license
CNone, they must obtain a U.S. license
DThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

SelectAnswer
ATo prevent the satellite from emitting out-of-band signals
BTo prevent creating errors in the satellite telemetry
CTo avoid reducing the downlink power to all other users
DTo avoid interfering with terrestrial QSOs

8. - E2B16

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

SelectAnswer
APAL
BNTSC
CScottie
DDRM

9. - E2C09

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

SelectAnswer
AA 2 meter VHF transceiver with a 1200 baud modem
BA standard wireless router running custom software
CAn optical cable connection between the USB ports of 2 separate computers
DA 440 MHz transceiver with a 9600 baud modem

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

SelectAnswer
ATo store digital messages in the satellite for later download by other stations
BTo delay download of telemetry between satellites
CTo upload operational software for the transponder
DTo relay messages between satellites

11. - E2E06

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

SelectAnswer
A1200 baud
B48 baud
C110 baud
D300 baud

12. - E3A14

From the contiguous 48 states, in which approximate direction should an antenna be pointed to take maximum advantage of aurora propagation?

SelectAnswer
AEast
BWest
CSouth
DNorth

13. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
APropagation away from the great circle bearing between stations
BSignals reflected back toward the transmitting station
CSuccessive ionospheric reflections without an intermediate reflection from the ground
DPropagation across the geomagnetic equator

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

SelectAnswer
ABy approximately 15 percent of the distance
BBy approximately twice the distance
CBy approximately 50 percent of the distance
DBy approximately four times the distance

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

SelectAnswer
AA wattmeter
BA time-domain reflectometer
CA logic analyzer
DA spectrum analyzer

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

SelectAnswer
AThere is an impedance mismatch between the antenna and feed line
BThe transmitter is not properly neutralized
CThere is possibly a short to ground in the feed line
DThere is more power going into the antenna

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

SelectAnswer
AIt decreases receiver third-order intermodulation distortion dynamic range
BIt limits the receiver's ability to receive strong signals
CIt reduces receiver sensitivity
DIt can cause strong signals on nearby frequencies to interfere with reception of weak signals

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

SelectAnswer
ADecrease the RF bandwidth of the receiver
BIncrease the receiver front end gain
CSwitch from fast AGC to slow AGC
DRaise the receiver IF frequency

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

SelectAnswer
AHarmonics of the AC power line frequency
BAn electrical-sparking signal
CA differential-mode signal at the AC power line frequency
DA common-mode signal at the frequency of the radio transmitter

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. - 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?

SelectAnswer
A14 degrees with the voltage leading the current
B76 degrees with the voltage leading the current
C14 degrees with the voltage lagging the current
D76 degrees with the voltage lagging the current

22. - E5C12

If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?

SelectAnswer
AIt contains resistance and inductive reactance
BIt has to be a direct current circuit
CIt contains resistance and capacitive reactance
DIt is equivalent to a pure resistance

23. - E5D15

What is the power factor of an R-L circuit having a 45 degree phase angle between the voltage and the current?

SelectAnswer
A1.0
B0.707
C0.866
D0.5

24. - E6A06

What is the beta of a bipolar junction transistor?

SelectAnswer
AThe switching speed of the transistor
BThe frequency at which the current gain is reduced to 1
CThe breakdown voltage of the base to collector junction
DThe change in collector current with respect to base current

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C04

What is the primary advantage of tri-state logic?

SelectAnswer
AMore efficient arithmetic operations
BLow power consumption
CAbility to connect many device outputs to a common bus
DHigh speed operation

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
ASteel-core toroids
BFerrite beads
CButterworth filters
DElectrolytic capacitors

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

SelectAnswer
A450 ohms
B300 ohms
C10 ohms
D50 ohms

29. - E6F06

Which of these materials is affected the most by photoconductivity?

SelectAnswer
AA heavy metal
BA crystalline semiconductor
CAn ordinary metal
DA liquid semiconductor

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

SelectAnswer
AAstable multivibrator
BMonostable multivibrator
CJ-K flip-flop
DT flip-flop

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

SelectAnswer
AA matched load resistor to prevent damage by switching transients
BA temperature compensating load resistor to improve linearity
CA high-pass filter to compensate for low gain at low frequencies
DA low-pass filter to remove switching signal components

32. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with minimal stop band ripple
BGradual passband rolloff with extreme stop band ripple
CExtremely flat response over its pass band with gradually rounded stop band corners
DExtremely sharp cutoff with one or more notches in the stop band

33. - E7D06

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

SelectAnswer
AIt increases the current-handling capability of the regulator
BIt provides negative feedback to improve regulation
CIt provides a constant load for the voltage source
DIt provides D1 with current

34. - E7E03

How does an analog phase modulator function?

SelectAnswer
ABy varying the tuning of a microphone preamplifier to produce PM signals
BBy varying the tuning of an amplifier tank circuit to produce PM signals
CBy varying the tuning of a microphone preamplifier to produce AM signals
DBy varying the tuning of an amplifier tank circuit to produce AM signals

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

SelectAnswer
AAdd 3 to each input value and subtract 4 from each output value
BMultiply each sample value by a factor of 3/4
CInterpolate by a factor of three, then decimate by a factor of four
DChange the gain by a factor of 3/4

36. - E7G03

What is the typical input impedance of an integrated circuit op-amp?

SelectAnswer
A1000 ohms
B100 ohms
CVery high
DVery low

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

SelectAnswer
ATaft, Hartley and Pierce
BColpitts, Hartley and Pierce
CPierce, Fenner and Beane
DTaft, Pierce and negative feedback

38. - E8A04

What is "dither" with respect to analog to digital converters?

SelectAnswer
AAn abnormal condition where the converter cannot settle on a value to represent the signal
BAn error caused by irregular quantization step size
CA small amount of noise added to the input signal to allow more precise representation of a signal over time
DA method of decimation by randomly skipping samples

39. - E8B09

What is meant by deviation ratio?

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

40. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

SelectAnswer
A0.3 kHz
B0.1 Hz
C0.5 kHz
D1.0 kHz

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
BBaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
CBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
DBaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

SelectAnswer
ATo calculate the front-to-side ratio of the antenna
BTo match impedances in order to minimize standing wave ratio on the transmission line
CTo measure the near-field radiation density from a transmitting antenna
DTo calculate the front-to-back ratio of the antenna

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

SelectAnswer
APolar plots of the far field elevation and azimuth patterns
BSWR vs frequency charts
CAntenna gain
DAll of these choices are correct

44. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

SelectAnswer
AThe main lobe takeoff angle increases in the downhill direction
BThe main lobe takeoff angle decreases in the downhill direction
CThe horizontal beam width decreases in the downhill direction
DThe horizontal beam width increases in the uphill direction

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?

SelectAnswer
AThe radiation resistance increases and the capacitive reactance decreases
BThe radiation resistance increases and the capacitive reactance increases
CThe radiation resistance decreases and the capacitive reactance decreases
DThe radiation resistance decreases and the capacitive reactance increases

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

SelectAnswer
AReflection coefficient
BVelocity factor
CDielectric constant
DCharacteristic impedance

47. - E9F11

What impedance does a 1/8 wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AA capacitive reactance
BThe same as the input impedance of the final generator stage
CThe same as the characteristic impedance of the line
DAn inductive reactance

48. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
APoints with constant resistance
BSWR
CPoints with constant reactance
DFrequency

49. - E9H06

What is the triangulation method of direction finding?

SelectAnswer
AA fixed receiving station plots three headings to the signal source
BThe geometric angles of sky waves from the source are used to determine its position
CAntenna headings from several different receiving locations are used to locate the signal source
DA fixed receiving station uses three different antennas to plot the location of the signal source

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

SelectAnswer
AUranium Hexafluoride
BMica
CBeryllium Oxide
DZinc oxide

Figure E7-3