SECTION ONE — Introduction
•connecting the 491 to a transducer (see also the Transducer Connec- tor
•troubleshooting and testing the system
•technical specifications for the 491
For information about obtaining technical support and returning the 491 for factory service, “SECTION FOUR — Troubleshooting and servicing the 491” beginning on page 21.
For details about operating the 491, see the Northstar 491 Echo Sounder Operations Manual (GM494) or Northstar 6000i’s Reference Manual, for that product.
Installation considerations
CAUTION!
The following list of installation considerations isn’t a substitute for all the details in Section Three. To ensure that you meet all critical installation parame- ters, be sure to read that entire section and follow all of its recommendations.
1.Check the shipping carton for any damage, and immediately report any damage to the carrier. Save all packing material in case you have to return the 491 to the factory for repair or evaluation.
2.Unpack the carton, and check its contents. You should have received:
•the Northstar 491 Echo Sounder
•
•
•491 parts kit (containing transducer cable end connector, back- shell, heatshrink tubing, and the Transducer Connector Instruc-
•Northstar 491 Echo Sounder Installation Manual (GM495)
•Northstar 491 Echo Sounder Operations Manual (GM494)
•owner registration card
3.Fill out the owner registration card and mail it to Northstar.
4.Review all of the installation requirements as outlined in Sections Two and Three.
5.Install the transducer, then terminate the cable (see ”Connecting the 491 to a transducer” starting on page 18).
6.Mount the 491. For instructions, see ”Mounting the 491” beginning on page 14.
7.Connect the 491 to ship’s power and to the navigator. Connection information begins on page 15.
With the vessel in the water, turn on the system and verify proper opera- tion.
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