Tag Archives: speaker as a microphone

Preamp for Speakers as a Microphone 2

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The previous Preamp for the speakers as a microphone installation is indeed simple, but has virtually no gain. It is quite possible to add a second transistor to fill the gap, as shown in above diagram. Note that the resistor R1 serves as the polarization of the two transistors Q1 and Q2. At the same time, the transistor input matching has become an NPN. Parts list : R1 : 470 R3 :… Read more »

Preamp for Speaker as a Microphone

Schematic Diagrams      Comments Off on 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… Read more »