This is simple condenser mic preamp circuit is bringing to change the sound to electrical signals.Then the electrical signal that is to expand the force was then sent out to the speakers.
When raising the power supply 9-volt circuit and talking to the voices Microphone (MIC1) will change the sound to electrical signals,through to C1 the coupling signal C1 is blocked by DC not to pass. Therefore, the signal will pass through the C1 has a voice to cooperate with B of Q1And amplifier to power up the output on pin C through C2 coupling signal again, only through voice to convert into a headset,Electrical signal into sound.The R1 is a current limited to raising Microphone (MIC1) to fit R2. It is held bias feedback signal from output to input, by to bestride between pin B and pin C of the transistor Q1.To provide stability for the good work.The R3 and R4 serve to help maintain enough voltage to properly bias.
This circuit is not design PCB. If you do not want to design own PCB. Or use universal PCB Board that difficult.
I would recommend a CanaKit UK009 – Electret Microphone Amplifier kit. It is a DIY Kits available for use. I hope this guide is helpful for you.
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