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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	Yes, the displayed frequency is within the 80 meter CW band segment
B	Yes, the DX station initiated the contact
C	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz
D	No, one of the sidebands of the CW signal will be out of the band

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 53 dB below
B	At least 73 dB below
C	At least 63 dB below
D	At least 43 dB below

3. - E1C04

What is meant by IARP?

Select	Answer
A	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
B	An indication of increased antenna reflected power
C	The internal amateur radio practices policy of the FCC
D	A forecast of intermittent aurora radio propagation

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
B	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
C	An amateur station located more than 50 km above the Earth's surface
D	An amateur station that transmits telemetry consisting of measurements of upper atmosphere

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Send the application form to the FCC and inform the FCC of the grade
B	Destroy the application form
C	Maintain the application form with the VEC's records
D	Return the application document to the examinee

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Technician, General, Advanced or Amateur Extra Class operators
B	Only Amateur Extra Class operators
C	Only General, Advanced or Amateur Extra Class operators
D	Any licensed amateur operator

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The point of minimum height of a satellite's orbit
B	The time it takes for a satellite to complete one revolution around the Earth
C	The time it takes for a satellite to travel from perigee to apogee
D	The point of maximum height of a satellite's orbit

8. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
B	A type of modulation in which one sideband is inverted
C	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
D	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	All of these choices are correct
B	To separate the calling stations from the DX station
C	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
D	To improve operating efficiency by reducing interference

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Node hopping
B	Multi-satellite relaying
C	Digipeating
D	Store-and-forward

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Audio FSK can be performed anywhere in the transmit chain
B	Direct FSK applies the data signal to the transmitter VFO
C	Audio FSK has a superior frequency response
D	Direct FSK uses a DC-coupled data connection

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	10 MHz - 14 MHz
B	220 MHz - 450 MHz
C	28 MHz - 148 MHz
D	1.8 MHz - 1.9 MHz

13. - E3B11

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

Select	Answer
A	Any time
B	Around sunset
C	Early evening
D	Around sunrise

14. - E3C07

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

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

15. - E4A03

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

Select	Answer
A	A logic analyzer
B	A wattmeter
C	A time-domain reflectometer
D	A spectrum analyzer

16. - E4B13

Which S parameter is equivalent to forward gain?

Select	Answer
A	S12
B	S21
C	S22
D	S11

17. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?

Select	Answer
A	Easier for front-end circuitry to eliminate image responses
B	Improved receiver noise figure
C	Reduced drift
D	Fewer components in the receiver

18. - E4D02

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

Select	Answer
A	Cross-modulation of the desired signal and desensitization from strong adjacent signals
B	Oscillator instability and severe audio distortion of all but the strongest received signals
C	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
D	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband

19. - E4E08

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

Select	Answer
A	Harmonics of the AC power line frequency
B	A common-mode signal at the frequency of the radio transmitter
C	A differential-mode signal at the AC power line frequency
D	An electrical-sparking signal

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	157.8 Hz
B	23.67 kHz
C	47.3 kHz
D	315.6 Hz

21. - E5B03

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

Select	Answer
A	The sign is reversed
B	The susceptance phase angle is the inverse of the reactance phase angle
C	It is unchanged
D	It is shifted by 90 degrees

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	+jX
B	-jX
C	Omega
D	X

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By multiplying the reactive power times the power factor
B	By dividing the reactive power by the power factor
C	By dividing the apparent power by the power factor
D	By multiplying the apparent power times the power factor

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Donor impurity
B	Acceptor impurity
C	Insulator impurity
D	N-type impurity

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Reverse bias
B	Inductive bias
C	Forward bias
D	Zero bias

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	A PGA contains its own internal power supply
B	Many similar gates are less expensive than a mixture of gate types
C	Complex logic functions can be created in a single integrated circuit
D	All of these choices are correct

27. - E6D10

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

Select	Answer
A	Toroidal cores have lower Q characteristics
B	Toroidal cores exhibit greater hysteresis
C	Toroidal cores make it easier to couple the magnetic energy into other components
D	Toroidal cores confine most of the magnetic field within the core material

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It is a CMOS analog-to-digital converter
B	Its phase shift changes rapidly with frequency
C	It samples an analog signal and passes it in stages from the input to the output
D	It is used in a battery charger circuit

29. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A device which measures the strength of a beam of light using analog to digital conversion
B	A digital encryption device often used to encrypt spacecraft control signals
C	A device which detects rotation of a control by interrupting a light source with a patterned wheel
D	A device for generating RTTY signals by means of a rotating light source

30. - E7A10

What is a truth table?

Select	Answer
A	A list of inputs and corresponding outputs for a digital device
B	A diagram showing logic states when the digital device output is true
C	A table of logic symbols that indicate the high logic states of an op-amp
D	A table of logic symbols that indicate the logic states of an op-amp

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

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

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	The Q of Pi-networks can be varied depending on the component values chosen
B	Pi-networks have fewer components
C	L-networks cannot perform impedance transformation
D	Pi-networks are designed for balanced input and output

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

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	For higher efficiency
B	To remove third-order distortion products
C	To reduce impulse noise reception
D	For compatibility with transmitters using phase modulation

35. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Reducing the effective sample rate by removing samples
B	Converting data to binary code decimal form
C	Removing unnecessary significant digits
D	Attenuating the signal

36. - E7G03

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

Select	Answer
A	100 ohms
B	1000 ohms
C	Very low
D	Very high

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Colpitts, Hartley and Pierce
B	Taft, Hartley and Pierce
C	Pierce, Fenner and Beane
D	Taft, Pierce and negative feedback

38. - E8A05

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

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

39. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	0.3
B	3
C	3000
D	1000

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	5.76 kHz
B	9.6 kHz
C	15.36 kHz
D	4.8 kHz

41. - E8D10

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

Select	Answer
A	Baudot 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
B	Baudot 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
C	Baudot 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
D	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A03

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

Select	Answer
A	To measure the near-field radiation density from a transmitting antenna
B	To calculate the front-to-back ratio of the antenna
C	To calculate the front-to-side ratio of the antenna
D	To match impedances in order to minimize standing wave ratio on the transmission line

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	14 dB
B	24 dB
C	18 dB
D	36 dB

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole configured to provide forward gain
B	A dipole one-quarter wavelength long
C	A dipole consisting of one wavelength of wire forming a very thin loop
D	A type of ground-plane antenna

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Improved radiation efficiency
B	Greater structural strength
C	Higher losses
D	Lower Q

46. - E9E04

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

Select	Answer
A	To provide a rejection notch that prevents the radiation of harmonics
B	To transform the antenna impedance to a higher value
C	To provide DC isolation between the feed line and the antenna
D	To cancel the inductive reactance of the matching network

47. - E9F04

What is the typical velocity factor for a coaxial cable with solid polyethylene dielectric?

Select	Answer
A	0.66
B	0.30
C	0.10
D	2.70

48. - E9G08

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

Select	Answer
A	Reassigning impedance values with regard to the prime center
B	Reassigning resistance values with regard to the reactance axis
C	Reassigning prime center with regard to the reactance axis
D	Reassigning reactance values with regard to the resistance axis

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	High-radiation angle
B	A very sharp single null
C	Broad band response
D	A very sharp peak

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?

Select	Answer
A	Mica
B	Beryllium Oxide
C	Zinc oxide
D	Uranium Hexafluoride

Figure E9-1