You are purchasing a microphone audio AGC sound level PCB.  This listing is for the bare PCB only.  No other parts are included.  Please see link below for schematic and parts info.  

This circuit provides audio AGC for audio input signals to provide a consistent audio output level.  One op-amp provides the audio AGC control before inputting the signal into the amplifier.  Another op-amp turns the audio signal into digital square waves for interface with other audio control products.  This module is very useful when viewing online media such as from YouTube.  The audio from ads or action scenes maybe very loud and the normal audio/voice maybe quiet.  The PEAGM module provides fast response to limit the loud sounds and increases gain for the low sounds.  It also works well as a microphone module for sound recordings.

Features:

- Simple transistor and op-amp design

- AGC audio signal level

- Electret microphone pre-amp circuit
- Adjustable output level

- Op-amp buffered output
- In-circuit fixed voltage regulator.

- Use standard components

- Output signal level LED

- Easy-to-use integrated design

- Small and economical

- Multi-function for DIY projects

PCB specification: 

1.  1/16” FR4 type, ROHS and lead-free. 

2.  Through-hole plated, double-sided copper traces, HASL coated holes. 

3.  Easy to read silkscreen labels.

4.  Robust design, reliable operation. 

5.  2.22"x1.22" +/- 0.01".

Available Model

PCB-PEAGM: PCB, automatic gain module, microphone, audio, 12V.  No parts, not assembled. All electronic parts to populate the PCB are available from Digi-Key.  Parts kit available.  Please contact us at on-sales(at)Onstatetech(dot)com for larger quantities or question on your application.  

Parts shipped in this listing: 1xPCB-PEAGM, 1x BOM listing.

Product info/data:
Full schematic, parts, low signal audio: Schematic PEAGM AGC audio.pdf

Basic schematic, parts, low level audio: Schematic PEAGM AGC audio basic.pdf
Youtube in/out signal test video.: AGM AGC Youtube video

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