Spark Electronics ELECTRET MICROPHONE 9*7MM

A Mathematical Explanation Moving Coil Microphone Electret Microphone Circuit Pre-Amplifier Circuit Possible Layout Looking for to buy electret microphone amplifier onlineMikroelectron.com give a electret microphone with high quality with best material @ JD1.00.electret microphoneBuy electret microphone online This device has a microphone and pre-amplifier built into a small enclosure. It is important to connect it the right way round because the built-in preamp might be destroyed otherwise. The preamp uses a field effect transistor (FET). This microphone uses two metal plates as a capacitor. One of the plates moves or vibrates in step with incoming sound waves. This causes the capacitance to change. Q = CV Q = charge (Coulombs) C = capacitance (Farads) V = voltage (Volts) Since Q stays constant (it does not have time to change) and since C changesit follows that V will change. Thus incoming sound waves are converted into a proportional alternating voltage. This voltage is amplified by the built-in FET. (B.5)