AUDIO AMPLIFICATION/A5000.

TM 11-5820-401-34-3/0967-LP-432-3060

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AUDIO AMPLIFICATION/A5000.

A block diagram showing a simplified layout of the A5000 tray is contained in F0-12. Refer to the

foldout while reading the information in this paragraph.

FILTER FL5001

Audio signals from the preamplifier are applied to low-pass Filter FL5001, which filters noise compo-

nents above 3000 Hz.

MONITOR AMPLIFIER A5100

Output from the FL5001 filter is applied directly to the monitor amplifier. The monitor amplifier's output

is a low-level audio signal of constant amplitude (under 1 vac), due to the absence of any volume

control on its input.

AUDIO AMPLIFIER A5100

The audio amplifier receives its input through the VOLUME control which attenuates signal amplitude

to control the amplifier's gain. Amplified audio from the A5100 is then applied to the power amplifier.

A biasing voltage of 16 vdc must be applied to the audio amplifier for it to function. This can be seen in

the following illustration, which shows a simplified version of the biasing circuit.

With no audio signals from Filter FL5001, 16 vdc flows through R5110, charges C5104, flows through

CR5102, and through the volume control resistor to ground.

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