Extension cables are required to put instruments at sites of interest and/or away from problematic sites, such as other instruments or unwanted acoustic sources.
Fiber-optic extension cables will be required to bring the power, Ethernet communications, and precision timing from the node to instrument sites more distant than about 100 m from the primary node or a secondary junction box. The design and implementation of such extension interfaces are an important step forward in seafloor observatory technology and will enable increased numbers of experiments to be ultimately incorporated via guest connectors on secondary junction boxes. One design is underway at the Applied Physics Lab for the NSF-supported Aloha/MARS cabled mooring. This project is funded to design and fabricate a secondary junction box and a 2 km extension cable with electro-optical converters (see http://alohamooring.apl.washington.edu/). An MBARI-funded 2005 project is also working on designs for extension cables and for Science Instrument Interface Modules. The latter SIIM design would provide guidance in connecting instruments that are serial and require a different voltage than 48 VDC.
Further information will be provided as it becomes available.