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Table of Contents
Read Me First!...................................................................................1
Capabilities and Specifications: FishMark
®
640c ..............................2
SeaFinder
®
640c DF.............................................................................2
How Sonar Works................................................................................4
How to Use this Manual: Typographical Conventions.......................5
Arrow Keys.......................................................................................5
Keyboard ..........................................................................................5
Menu Commands.............................................................................5
Instructions = Menu Sequences......................................................5
Section 2: Installation & Accessories...........................................7
Preparations.........................................................................................7
Transducer Installation.......................................................................7
Recommended Tools and Supplies..................................................8
Selecting a Transducer Location.....................................................9
How low should you go?.................................................................10
Shoot-Thru-Hull vs. Transom Mounting......................................11
Transom Transducer Assembly and Mounting............................12
Trolling Motor Bracket Installation (single-frequency only).......19
Transducer Orientation and Fish Arches.....................................20
Shoot-Thru-Hull Preparation........................................................21
Testing Determines Best Location................................................22
Shoot-Thru-Hull Installation........................................................24
Speed/Temperature Sensors..............................................................26
Optional Speed Sensor Installation..................................................27
Power Connections.............................................................................29
Mounting the Unit: Bracket, In-Dash or Portable.......................31
Bracket Installation.......................................................................32
In-Dash Installation ......................................................................34
Portable Installation......................................................................34
Basic Sonar Operation..................................................................37
Keyboard............................................................................................37
Power/lights on and off......................................................................38
