An index detection unit detects the coordinate values of indices in a sensed image sensed by an image sensing device attached with an orientation sensor. The mercury sorbent is prepared by treating a carbonaceous substrate with an effective amount of a bromine-containing gas, especially one containing elemental bromine or hydrogen bromide, for a time sufficient to increase the ability of the carbonaceous substrate to adsorb mercury and mercury-containing compounds. The system also includes a test interface, or test PHY, configured for coupling to the physical interfaces for analysis of the data passing through those physical interfaces.