Instrument: Knudsen 320 BR deepwater echosounder

Dataset: 
alongtrack_AT15-61
Instrument: 
Knudsen 320 BR deepwater echosounder
Instrument Short Name: Knudsen 320
Community Standard Description
(http://vocab.nerc.ac.uk/collection/L05/current/156/)
Instrument Description:

The Knudsen 320 B/R deepwater echosounder is a digital data logging system used to measure water depth (e.g. depth of the seafloor). The system is configured to work with different frequency transducers. For example, the Edo 323 B is a 12 kHz High Frequency (HF) transducer or it can be configured to work with an array of 3.5 kHz Low Frequency (LF) transducers mounted in the hull of a vessel.

PI supplied instrument name: Knudsen 320 BR deepwater echosounder
Dataset-specific description

Knudsen bathymetry ( Knudsen) Depth to surface (meters).
Format:
$PKEL99,HF,xx.xx,cc.cc,LF,yy.yy,cc.cc,ssss,lat,lon
"HF" High freq header
xx.xx 12 kHz depth to surface using cc.cc & ssss corrections (meters)
cc.cc depth of 12 kHz transducer (meters)
"LF" Low freq header
yy.yy 3.5 kHz depth to surface using cc.cc & ssss corrections (meters)
cc.cc depth of 3.5 kHz transducer (meters)
ssss sound speed used for depth calculations (m/s)
Lat Latitude
Lon Longitude
Note - 12 kHz and 3.5 kHz transducers are at 5.95m (19.5 ft) depth on Atlantis.