LM386, MIC Help required

[gkulkarnii]

Hi All,

I am trying to build a clap recognizer. As a first step i am trying to amplify the output of electrut microphone. My circut is attached, which i found in this forum. I am getting amplified output as 0.65 volts which does not vary with "whatever sound i make!" and fades with time i.e after sometime the output becomes zero. I am checking the ac output in multimeter. What can be the possible problem?

I tried to break the circuit and just check whether stand alone microphone is giving desired output!. Circuit attached. Samething with this also. Output (1.3v) doesnt vary with sound and fades away.

I have checked the connections, capacitor polarity, LM386 connection, all are fine.

FIrst time when i connected circuit i connected all electrolyte capacitors in reverse directions. Capacitors might have gone bad, is that why this behaviour? Also while soldering microphone it got heated up (2 mics i have soldered) will that damage mic?

Im not electronics guy. Please help me move ahead. I will appreacite all your suggestions.

Thanks,
Guru

 

[ALERTLINKS]

You can connect a speaker to the output of lm386 after the capacitor and to the ground to monitor output. Pin 5 should be at 1/2 Vcc if circuit is build correct. The reading you are getting is charging of 220uF capacitor through multimeter.