Welcome To The Northstar Echo Sounder - NorthStar 972 Quickstart Manual And Reference Manual

Welcome to the Northstar Echo Sounder

How echo sounding works
An echo sounder produces high-voltage
electrical pulses (called "pings") that the
transducer converts into sound waves.
When a sound wave hits and reflects off an
object, such as fish, debris, seaweed, or the
seabed, the reflected sound wave (an
"echo") returns back to the transducer
along an imaginary vertical line called a
"water column." The transducer converts
this echo into a tiny electrical pulse. The
sounder digitizes these pulses and sends
them to the navigator, so that echo
sounding pictures of the water and seabed
can be displayed and analyzed on the echo
Reference Manual Revision B
CAUTION!
Proper installation and configuration of
your Northstar sounder is of utmost
importance for accurate and effective
performance under a variety of
conditions. To get the best performance,
Northstar strongly recommends
installation and set-up be performed by a
qualified marine technician. For
installation procedures, see the Northstar
Echo Sounder Installation Manual (Part
Number GM491).
sounder screen. The echo sounding system
lets you see a real-time cross section of
what's happening underneath your vessel.
The 491 module automatically turns on
and off as the 972 is turned on and off.
There is a 20-second delay after the 972
turns off before the 491 turns off.
Setting up the sounder
Your sounder should be installed by a quali-
fied marine technician. Your satisfaction
with the system's performance will be greatly
influenced by the practical knowledge and
experience of the installer. Unlike GPS or
other marine electronics systems, echo
sounder installation is as much an art as it
is a science.
The installation procedure includes setting
the 972's AUX port to the sounder option,
and then setting the following options.
Once properly set, they should not be
adjusted further.
the transducer's depth
•
the speed and temperature
•
the calibration for the speed sensor
•
the calibration for the temperature
•
sensor
the gain calibration for the transducer
•
Reference section 7 — Echo sounding

Welcome to the Northstar Echo Sounder

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