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View Full Version : hooking up an electret microphone



science_geek
03-16-2009, 09:20 AM
i have been doing well lately interfacing sensors, i have 4 piezo tabs hooked up and an ambient light sensor and i have it graphing the ouput of the sensors, kind of cool to see the frequency of light with a sensor and to be able to "feel" the footsteps from across my house, but anyway, i was trying to hook up an electret microphone and no matter what i did i got nothing, is there a way to hook it up to measure frequency and/or amplitude of a sound with/without the use of an adc,

Fred Hawkins
03-16-2009, 09:46 AM
take a look at the Propeller Demo board schematic.

kwinn
03-16-2009, 09:49 AM
Here is a simplified schematic. With an op amp or transistor to amplify the output you can use a single pin to measure the frequency, and the 2 pin ADC circuit to measure amplitude.

CRocket
10-28-2010, 06:15 AM
i have been doing well lately interfacing sensors, i have 4 piezo tabs hooked up and an ambient light sensor and i have it graphing the ouput of the sensors, kind of cool to see the frequency of light with a sensor and to be able to "feel" the footsteps from across my house, but anyway, i was trying to hook up an electret microphone and no matter what i did i got nothing, is there a way to hook it up to measure frequency and/or amplitude of a sound with/without the use of an adc,

Hey science_geek did you ever get that electret mic to work with the propeller? If so, I'm having the same problem. I built several circuits and none of them work properly. One kind of worked but bargraph still didn't light up right; jumping segments. Another actually made bargraph change as I moved my hand closer to it. If you learn anything that could help, I'd appreciate the input. I've already spent way too much time on this one aspect of the Prop.

Loopy Byteloose
10-28-2010, 09:22 AM
The world seems to keep getting more complex. I presumed that all electret mikes are the same and there was pretty much one way to get output, but it seems that with the advent of cellular phones, some electret mikes have morphed and now include an amplifier/pre-amplifier chip within them.

That certainly would play havoc with just Googling for generic schematics.

http://www.epanorama.net/circuits/microphone_powering.html

Try the above link for 'standard hook-up'