Back again,
spent the night trying to work this out.
i've attached my circuit for comments (opens with Paint but not with MS Photoeditor for some reason!!). basically, its supposed to be ECG circuit, and i've included the HCNR200 opto as per the datasheets for basic isolation. Can someone have a look and see whether what i have done so far is correct?
i also want to take the output from here to a PIC microcontroller, i'm thinking i'll probably need some kind of protection to prevent voltages more than 5V going to the PIC. any ideas? i have no idea whatsoever cause i'm very new to electronics. thanks.