Small Electret Microphone Pre-amplifier

Small Electret Microphone Pre-amplifier
The mic pre amp described here is designed to connect a small electret microphone and uses an integrated circuit type NE5532. As you can see, this scheme is very simple. The use of a dual operational amplifier type NE5532 is a large part in simplicity, although it was quite possible to simplify even more by using a single transistor. (more…)

Preamp for Speaker as a Microphone

Preamp for Speaker as a Microphone
This Microphone Preamp circuit shows that it is possible to use the speaker as a microphone, and is specifically designed to beginners because of its simplicity. Power consumption, of about 2mA, allowing the circuit is operated a few hours on a single 9V battery. However, it does not prevent you to use a stable power supply, or solar cells ... (more…)

Microphone Preamplifier based TLC251

Microphone Preamplifier based TLC251
Mic Preamplifier described here is designed for dynamic type microphones, the impedance between 200 ohms and 1 ohm. Its uniqueness lies in the low power consumption, no more than 30 uA in the "worst" case, and make it very portable for this, powered by 1.5 V battery which will allow for longer operating time. This scheme is based on records from the Texas Instruments application. (more…)

Simple Microphone Pre-amp

Simple Microphone Pre-amp
This Simple preamplifier circuit provides sufficient gain to weak audio signals from the microphone. This circuit can also be supplied from the voltage baterry 3 to 9 volts if necessary. Take a note that the microphone used in this pre-amp circuit is electret type. (more…)