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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Propagation-Radio-Waves

Radio Wave Propagation types

Armature Winding ,Pole Pitch, Coil Span, Commutator Pitch

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Control Systems/Gain

What is Gain? Gain is a proportional value that shows the relationship between the magnitude of the input to the magnitude of the output signal at steady state. Many systems contain a method by which the gain can be altered, providing more or less "power" to the system. However, increasing gain or decreasing gain beyond a particular safety zone can cause the system to become unstable. Consider the given second-order system: We can include an arbitrary gain term, K in this system that will represent an amplification, or a power increase: In a state-space system, the gain term k can be inserted as follows: The gain term can also be inserted into other places in the system, and in those cases the equations will be slightly different. Example: Gain Here are some good examples of arbitrary gain values being used in physical systems: Volume Knob On your stereo there is a volume knob that controls the gain of your amplifier circuit. Higher levels of v...

Electrical Engineering

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