The NL844 is a 4 channel AC coupled preamplifier which replaces the NL824. Unlike the NL824, filter and gain settings are controlled in pairs (i.e. channels 1 & 2 and channels 3 & 4 share settings. As well as amplifying 4 channels, the unit can also be operated in a single or two channel mode (channels 1 & 3 or 2 & 4). The NL844 needs to be connected to the NL820A Isolator module.
For full web page, please see http://www.autom8.com/neurolog.html
Download a User's Manual at http://www.autom8.com/docs/NL824-844.pdf
Download a brochure at http://www.autom8.com/pdfs/amplifiers/NeuroLog.pdf