FREQUENCY-RESPONSE

BJT and JFET Frequency Response

Decibels

Power and audio levels are related on a log basis. That is an increase of power level, say from 4 to 16 does not increase the audio level by a factor of 16/4=4. rather it will increase the audio level by a factor 0f 2, as obtained by (4)2 =16.

To increase the audio level by a factor 3, the power level should be increased from 4 to (4)3 = 64.

Bell is defined by the following equation-

Bell is a too large unit, so decibel is used, as defined by,

dBm

P1 is accepted as 1mW, then

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