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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	No, the sideband will extend beyond the band edge
B	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz
C	Yes, because the displayed frequency is within the 20 meter band
D	Yes, because you were not the station calling CQ

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 63 dB below
C	At least 73 dB below
D	At least 43 dB below

3. - E1C07

What is meant by local control?

Select	Answer
A	Direct manipulation of the transmitter by a control operator
B	Automatically manipulating local station controls
C	Controlling a station through a local auxiliary link
D	Controlling a repeater using a portable handheld transceiver

4. - E1D03

What is a telecommand station in the amateur satellite service?

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

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	2
B	3
C	4
D	5

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	The transmission must not be used to obscure the meaning of any communication
B	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
C	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
D	All of these choices are correct

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	435 MHz - 438 MHz
B	144 MHz - 146 MHz
C	29.5 MHz - 29.7 MHz
D	50.0 MHz - 50.2 MHz

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	525
B	60
C	1080
D	30

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	At the top of each band, usually in a segment reserved for contests
B	In the weak signal segment of the band, with most of the activity near the calling frequency
C	In the middle of each band, usually on the national calling frequency
D	In the middle of the band, usually 25 kHz above the national calling frequency

10. - E2D04

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

Select	Answer
A	To store digital messages in the satellite for later download by other stations
B	To delay download of telemetry between satellites
C	To upload operational software for the transponder
D	To relay messages between satellites

11. - E2E03

How is the timing of JT65 contacts organized?

Select	Answer
A	Stations take turns on alternate days
B	By exchanging ACK/NAK packets
C	It depends on the lunar phase
D	Alternating transmissions at 1 minute intervals

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The F2 layer
B	The D layer
C	The E layer
D	The F1 layer

13. - E3B09

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

Select	Answer
A	Around the solstices, especially the winter solstice
B	Around the equinoxes, especially the spring equinox
C	Around the equinoxes, especially the fall equinox
D	Around the solstices, especially the summer solstice

14. - E3C01

What does the term ray tracing describe in regard to radio communications?

Select	Answer
A	Modeling a radio wave's path through the ionosphere
B	The process in which an electronic display presents a pattern
C	Evaluating high voltage sources for X-Rays
D	Determining the radiation pattern from an array of antennas

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	All of these choices are correct
B	Match the antenna to the load
C	Use high quality double shielded coaxial cables to reduce signal losses
D	Attenuate the transmitter output going to the spectrum analyzer

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High reluctance input
B	Low reluctance input
C	High impedance input
D	Low impedance input

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Frequency discrimination
B	Capture effect
C	Cross-modulation interference
D	Desensitization

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	Third-order intermodulation produces three products for every input signal within the band of interest
B	Third-order products are an indication of poor image rejection
C	The third-order intercept is much higher than other orders
D	The third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A clicking noise at intervals of a few seconds
B	The appearance of unstable modulated or unmodulated signals at specific frequencies
C	A loud AC hum in the audio output of your station receiver
D	A whining type noise that continually pulses off and on

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	315.6 Hz
D	47.3 kHz

21. - E5B06

What is susceptance?

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

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By Y and G values
B	By X and R values
C	By real and imaginary parts
D	By phase angle and amplitude

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

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To keep the gate voltage within specifications and prevent the device from overheating
B	To provide a voltage reference for the correct amount of reverse-bias gate voltage
C	To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
D	To protect the substrate from excessive voltages

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	A sub-harmonic pump signal
B	Forward DC bias current
C	Capacitance of an RF coupling capacitor
D	Reverse voltage larger than the RF signal

26. - E6C14

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

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

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Magnetizing current
B	Direct current
C	Excitation current
D	Stabilizing current

28. - E6E04

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

Select	Answer
A	10 ohms
B	300 ohms
C	450 ohms
D	50 ohms

29. - E6F12

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

Select	Answer
A	Protons
B	Electrons
C	Photons
D	Holes

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	A flip-flop
B	A clock
C	An "OR" gate
D	An "AND" gate

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Output load resistor
B	Emitter bypass
C	Self bias
D	Fixed bias

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	A special filter that emphasizes image responses
B	A variable bandwidth crystal lattice filter
C	An automatic notch filter
D	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	The conduction of a control element is varied to maintain a constant output voltage
B	The control element duty cycle is proportional to the line or load conditions
C	It has a ramp voltage as its output
D	It eliminates the need for a pass transistor

34. - E7E10

How does a diode detector function?

Select	Answer
A	By rectification and filtering of RF signals
B	By mixing signals with noise in the transition region of the diode
C	By breakdown of the Zener voltage
D	By sensing the change of reactance in the diode with respect to frequency

35. - E7F12

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

Select	Answer
A	Signal conditioning
B	Decimation
C	Quadrature mixing
D	Fast Fourier Transform

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. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Eliminating noise on the oscillator's power supply
B	Using the oscillator only for CW and digital signals
C	Use of NP0 capacitors
D	Mechanically isolating the oscillator circuitry from its enclosure

38. - E8A04

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

Select	Answer
A	A small amount of noise added to the input signal to allow more precise representation of a signal over time
B	An error caused by irregular quantization step size
C	A method of decimation by randomly skipping samples
D	An abnormal condition where the converter cannot settle on a value to represent the signal

39. - E8B09

What is meant by deviation ratio?

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

40. - E8C10

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

Select	Answer
A	It has more resolution than simple binary
B	It facilitates error detection
C	It has more possible states than simple binary
D	It increases security

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Ground loops
B	Bit errors in the modem
C	Excessive transmit audio levels
D	Excessive numbers of retries

42. - E9A08

What is meant by antenna bandwidth?

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

43. - E9B14

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

Select	Answer
A	Antenna gain
B	All of these choices are correct
C	SWR vs frequency charts
D	Polar plots of the far field elevation and azimuth patterns

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band trap antenna
B	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
C	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
D	A phased array antenna consisting of multiple loops

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth increases
B	SWR bandwidth decreases
C	More common-mode current is present on the feed line
D	Gain is reduced

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element reactance must be capacitive
B	The driven element reactance must be inductive
C	The driven element resonance must be lower than the operating frequency
D	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	The same as the input impedance to the generator
C	Very high impedance
D	Very low impedance

48. - E9G08

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

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

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It narrows the bandwidth of the received signal to improve signal to noise ratio
B	It compensates for the effects of an isotropic antenna, thereby improving directivity
C	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
D	It prevents receiver overload which could make it difficult to determine peaks or nulls

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Ingestion of ozone gas from the cooling system
B	Hearing loss caused by high voltage corona discharge
C	Blood clotting from the intense magnetic field
D	Localized heating of the body from RF exposure in excess of the MPE limits

Figure E7-1