I want to do a project on EMG(voltage that produce in action of the muscles) I search after electrical circuit for the (EMG) I search after recommended electrodes I want to do this project with micro controller Do I need to do FFT ? Where I can find FFT device that I can put near the micro controller ? I search any information a bout (EMG) that can help me

Google is a reasonably good source - http://advan.physiology.org/cgi/content/full/31/2/242 You may not need to do the fast fourier Transform, but read up and see - http://en.wikipedia.org/wiki/Fast_Fourier_transform http://www.electrodestore.com/

Thanks beenther I don't understand why I don't need to do FFT Also I search after more electrical circuit for the (EMG) And any information about (EMG) that can help me

Hallow dave Your question is my question if I know the answer I am not will ask it Maybe anybody here know about forums in biomedical ???

If you wish to record muscle data, then that is what you will do at the time. Later, if you wish to characterize that data, you may find that the FFT is useful. That decision has to be yours.

Hi Joni As other has mentioned some creative Gooling may provide you some useful circuits. try "electromyography circuit" or "emg circuit". But I can give you a tip that you should use circuits with FET input stage as you are doing measurement with a high source impedance. The EMG circuit is quite similar to the ECG circuit. You may or may not use a micro controller. If your circuit is some sort of school project. You may cut some corners using commercial AD board, and just build the EMG amplifier. And for the FFT. You do not use a FFT device. FFT is a mathematical algorithm. You implement it in software or firmware after the signal has been converted from analog to digital representation. This do not have to be so hard. Many tools like Labview or matlab have this functions the library.

I'm not sure your question is my question. You have said, "I don't understand why I don't need to do FFT"; not understanding why you don't means you must have a reason why you do think you need an FFT - clarification of why you think this is what I am asking. It then begs the question about the system you are considering, as others have said, the FFT is an implementation of a mathematical construct, and as such resides within a system. I'm just try to get some clarity on what background research you have done before I give you a more specific answer. Dave