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Elecret microphone connection
Elecret microphones have a small electret melement and FET amplifier built to same case. Electret microphones needs some power to operate. The power (typically 4-10V) is fed to microphone through resistor (typically 1-10 kohm). The electret microphone capsule takes typicaly 0.5-2 mA current when it operates.
vcc
O
|
/
\
/
\ EQUAL TO REQUIRED IMPEANCE
/ EX.= 1000 Ohm
\
|
| CAPACITOR MOST ANY VALUE 10uF 16v
|---| | + | /
| |---0----| |------- AUDIO OUT
| | | \
| |----O--------------
|---| |
|
-----
---
-
Here is another electret microphone powering shematic:
capacitor (0.5 uf or so)
| |
+---------------------+--------| |--------------> to amplifier
| | | |
| (positive lead) | _ _
| +----------/ \_/ \_/----------+
MIC (resistor 1-2K or so) |
| | +
| (ground lead) (-) -------
| (battery 9v or so) ---
| |
| |
+---------------------------------------------------+----> ground
to amp
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