maulik patel - 2016-05-03

Hi,
I am confused about electrodes connection which is common and DRL circuit .I am trying use one channel do i need DRL circuit and common circuit ? i f i am using passive electrodes then how many electrodes do i need ?and measuring signal can i see on scope ?and outout with respect to virtual ground or actual ground ?because passive electrodes has no amplifier and polarity that is why i am bit confused .Please can you advice me .
Thank you,
maulik patel