WHOI has 30 short period instruments that they operate as part of the OBSIP pool. The “D2” instruments were designed to be compact and light-weight to make recoveries and deployments quick, especially during active source experiments that require fast turnover. Data offload can be completed in closed-ball mode. They are equipped with a seismometer and hydrophone and a battery capacity of ~1 month active source (alkaline) or ~8 months recording at 100 Hz (lithium). The general characteristics of these instruments include:
− 24-bit analog-to-digital converter
− low-power, digitally-temperature-compensated (DTCXO) clock
− 20 Gb disk drive
− Geospace 3-axis 4.5 Hz geophone
− Ηigh Τech hydrophone