NorthStar Echo Sounder 491 Operation Manual page 73

491 Echo Sounder Operations Manual
Table 4: 491 echo sounder features (Continued)
Manual controls
Gain 0 to 75 db
Clutter 0 to 9
Signal level 0 to 5
Noise limiter ON/OFF
White level Any single color
Other Screen color palette
Depth marker
Position marker
Zoom in/out
Shift
Ranges 15, 30, 60, 120, 200, 400, 800, 1000, 2400 feet
5, 10, 20, 40, 80, 150, 300, 500, 800 meters
Advance 1/8 to 2/1
speed
Depth units Feet, meters, fathoms
Installation Include speed, temperature, gain, and transducer
calibrations type
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