Applications of Logarithms

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Applications of Logarithms

• Decibels Power Gain
• Decibels Voltage Gain
• Frequency and Gain
• Bode Plot
• Bode Plot - 2

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Decibels Power Gain
The decibel is the unit of measure we use when computing power gain. Pin 100 mW, Pout 30 W. Find Ap.
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Decibels Voltage Gain

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Frequency and Gain
Key Point As a straight-line approximation, the gain will change at the rate of 6 dB per octave and 20 dB per decade.
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Bode Plot
A Bode plot is a plot of gain versus frequency. As a straight-line approximation, the gain will change at the rate of 6 dB per octave and 20 dB per decade.
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Bode Plot - 2

If the mid-frequency gain is 25 dB, f1 is 90 Hz and f2 is 12 kHz. Construct a Bode plot.