Specifications
Channel Master Operation Manual
page 126 RD Instruments
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Main Lobe: The main focus of energy emitted from a transducer. If the
transducer were a flashlight, the main lobe would be the visible beam of
light.
Mariner: Model name for a Workhorse Monitor ADCP configured for un-
derway current measurement in shallow water (as opposed to the deep water
Ocean Surveyor systems).
Modes: RDI offers several modes of operation that are optimized for cer-
tain conditions. There are currently five modes of operation for water pro-
filing available from RDI:
Mode 1: General purpose water profiling. This is the most robust
profiling mode, designed for the widest variety of measurement ap-
plications. Mode 1 can resolve high velocities and can measure over
long ranges.
Mode 5: For high resolution profiling in shallow water with low
flows. Mode 5 should be used with bottom tracking. It offers the
lowest standard deviation per measurement, but is also the most lim-
ited in its allowed performance envelope (e.g. low velocity flow,
slow platform movement, no high shears or turbulence).
Mode 8: Also for high resolution profiling in shallow water. Mode
8 should also be used with bottom tracking. It has higher standard
deviation per measurement than mode 5, but allows a somewhat
wider performance envelope.
Mode 11: The latest in our high resolution profiling modes. In-
tended for the shallowest water, it is also well suited for boundary
layer studies. Mode 11 should be used with bottom tracking. It al-
lows smaller depth cells (1 cm), more depth cells, and has improved
signal processing which allows faster ping rates and a wider per-
formance envelope than modes 5 and 8. Mode 11 is intended to su-
percede mode 5.
Mode 12: Offers increased resolution (1 cm depth cells) and uses
multiple sub-pings to improve the standard deviation of each meas-
urement. Mode 12 allows measurement of fast moving, shallow wa-
ter; and can also be used to improve the standard deviations of any
measurement (any range, any velocity) when the ADCP heading is
fixed or reasonably steady.
Monitor: Model name for a direct reading Workhorse ADCP.
Moving Bottom: Some rivers carry such a heavy sediment load that they
do not have a clearly identifiable bottom. In essence, the mud just keeps
getting thicker and slower with depth. In such environments it is not un-