The HP 16515A/16516A module is a high-speed timing analyzer with up to a 1 GHz sample rate that plugs into the HP 16500A Logic Analysis System mainframe. The HP 16515A is the master card, offering the user a 1 GHz sample rate on 16 channels with 8k of memory per channel. The HP 16516A expansion card offers an additional 16 channels for a maximum of 32 channels per module set or 80 channels per HP 16500A (with the appropriate combination of HP 16515A and HP 16516A cards).