Instrument: D&A Instruments Optical Backscatter Sensor OBS-3

Optical backscatter instrument measuring scattering in water between 140 - 160 deg for a wavelength of 875nm. It has a turbidity range of 0-2000 FTU and a maximum working depth of 500m. This instrument was superseded by the OBS-3+ model in 2005. The D and A Instrument Company and its OBS product line were purchased by Campbell Scientific Inc who now has full responsibility for D and A Instruments.