FARB/PTRB telemetry

During the past year, the BSL received notice that the government-owned radio facility atop Mt Tamalpais in Marin County would be privatized. At the Mt Tamalpais facility, the BSL operated digital radio telemetry to the station FARB located on the Farallon Islands west of the Golden Gate, and PTRB (the BARD GPS) site at Point Reyes.

Access to the Mt Tamalpais radio facility began in the early 1990's. Initially, digital data from the station ARC and later HOPS was telemetered via the USGS-operated microwave system there. In March of 1997, the BSL worked with the USGS to establish radio connections to FARB and later PTRB from Mt Tamalpais, with a frame-relay circuit back to UC Berkeley.

Concurrently, in November of 2004, the managing biologist from USFW contacted the BSL's engineers for assistance with the radio telephone at the Farallon's. The license to operate their 30-year-old equipment was expiring and, worse, their mainland repeater site at a firehouse on the Marin county coast was scheduled to be removed. Without the radio phone, there would be no voice communications to the islands.

BSL engineers began a search for a site on the mainland which could accommodate radio telemetry from both the seismic instrumentation and the new voice circuit. The new location would need line-of-sight to the Farallon's and have existing phone services. With only a few months to identify and permit the new location, an obvious choice was the University of California at San Francisco (UCSF). After contacting UCSF physical plant, a rooftop location was found and an internal University agreement put in place.

The BSL engineers designed, built, and tested communications systems for both the BSL and USFW. Two separate radio links were installed. The BSL radio link is connected to a frame-relay circuit; the USFW radio link is connected to a digital subscriber line (DSL). The BSL engineers used wireless Ethernet bridge radios to effectively extend the DSL service to the Farllons, providing high-quality voice and Internet connectivity. Biologists on the island can now transfer files and images, send email and faxes, access the Internet, and make simple telephone calls. The collaborative efforts and solution between BSL, UCSF, Point Reyes Bird Observatory, and the US Fish and Wildlife Service are shown schematically in Figure 3.5

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