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Electronic Circuits

MULTI STAGE AMPLIFIERS

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Electronic Circuits

There are several different multi-stage amp circuits that function as dc-amps.

1) COMPLIMENTARY AMPLIFIER

2) DARLINGTON AMPLIFIER

3) DIFFERENTIAL AMPLIFIER

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Electronic Circuits

COMPLIMENTARY AMPLIFIERS

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Electronic Circuits

DARLINGTON AMPLIFIERS

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Electronic Circuits

DIFFERENTIAL AMPLIFIERS

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Electronic Circuits

Typically referred to as (audio frequency amps) or audio amplifiers.

These amps are used to amplify the audio spectrum, utilizing class A operation.

Class A operates at the full 360 degree wave form.

RC coupled and transformer coupled.

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Electronic Circuits

RC COUPLED AUDIO AMPLIFIER

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Electronic Circuits

Transformer coupled stages are more efficient, therefore it is used more often.

Transformers provide isolation between stages and matches output and input impedances for a minimum of loading.0

This provides maximum transfer of power.

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Electronic Circuits

TWO STAGE TRANSFORMER COUPLED AUDIO AMPLIFIER

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Electronic Circuits

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Electronic Circuits

TRANSFORMER TYPE, PUSH PULL POWER AMPLIFIER

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Electronic Circuits

Video amps must be a wide band amplifier.

Video signals range from 10hz to 5mhz.

Video amps are typically RC coupled amps.

An inductor is added to the coupling circuit for frequency compensation.

Common-emitter circuits are used for amplification.

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Electronic Circuits

VIDEO AMPLIFIER

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Electronic Circuits

Radio frequency and intermediate frequency.

The radio frequency band ranges from 10khz to 30,000mhz.

The RF amp amplifies these radio frequencies received by an antenna then amplify that received signal.

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Electronic Circuits

BLOCK DIAGRAM OF A TYPICAL RECEIVER