K2 Strong Motion Accelerograph

A closer view of the internals of the K2 accelerograph. The metal bar in the lower left hand corner of the case is the battery holder. The three ground motion sensors (for vertical, N-S, and E-W motions) are in the top left hand corner of the device, covered by a protective grille. The data conversion/storage/communications hardware is in the right half of the device. The orange rectangular object to the left is the rechargeable battery which powers the K2 during power shortages.