Raymarine DSM250, Owner'S Handbook Manual

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Chapter 1: Overview 1-1
Chapter 1: Overview
1.1 Introduction
This handbook describes the DSM250 Digital Sounder Module.
The DSM250 receives sonar signals from a transducer mounted in
the water and transmits data via
hsb 2
to a Pathfinder PLUS Radar
or Chartplotter display unit already installed in your vessel, elimi-
nating the need for a separate display unit. You may also connect
the module to an existing PLUS Fishfinder display for improved
performance.
Note: Older HSB (non-PLUS) display units must be upgraded to hsb
2
before they can function with the DSM250.
Figure 1-1: DSM250 Digital Sounder Module
The DSM250 employs a very high transmission repetition or
“ping” rate which, along with the digital adaptive high sample
rate receiver, ensures that fish and bottom structure are presented
in superb detail and optimal color allocation (in color LCD dis-
plays). The DSM250 digital bandwidth adaptation adjusts the
receiver band width dynamically from very wide to very narrow,
as required by the actual water conditions. This provides superior
fish and bottom detection in conditions where other fishfinders
see very little or nothing at all.
D61
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