When a decibel value is computed by comparing a power value to 1 mW it is called as? - Avionics MCQ

Aeronautical & Aerospace Engineering : Avionics - Quiz(MCQ)

When a decibel value is computed by comparing a power value to 1 mW it is called as?

A)

dB

B)

dBm

C)

DB

D)

dBc

Correct Answer : dBm

Explanation : When the gain or attenuation of a circuit is expressed in decibels, implicit is a comparison between two values, the output and the input. An often used reference level in communication is 1 mW. When a decibel value is computed by comparing a power value to 1 mW, the result is a value called the dBm. It is computed with the standard power decibel formula with 1 mW as the denominator of the ratio.

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What is the peak value of 5th harmonic if the square wave has a peak voltage of 3v and a frequency of 48Khz?

A)

0.52

B)

0.74

C)

0.76

D)

1.5

Correct Answer : Option (C) : 0.76

Explanation : avionics

Which instrument produces frequency domain information?

A)

Oscilloscope

B)

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C)

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D)

Spectrum analyzer

Correct Answer : Option (D) : Spectrum analyzer

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A pulse train has a rise time of 6 ns. What is the minimum bandwidth to pass this pulse train faithfully?

A)

41.5MHz

B)

42.6MHz

C)

58.3MHz

D)

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Correct Answer : Option (C) : 58.3MHz

Explanation :

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