Hi, I'm Manuel Ibañez, i'm a biomedical engineer from Colombia, i had been working on biosigal processing during 3 years at the university projects, i did a prosthetic finger with EMG control, i can desing the circuit in five days or less, giving you a circuit schematic for a late implementation, please tell me about the project specifications, like if you need a patient electrical protector inside the circuit, or if you need that the instrumental amplifier be an amplifier arragment or a chip like the AD620; the circuit will be form by a patient adquisitor, instrumental amplifier, band pass filter stage, final amplifier stage, and finaly an offset for the digitalization with a micro, i will be in atention for your messages, thanks a lot