Technical information
Table Of Contents
- PART1.pdf
- PART2.pdf
- OPERATION OF THE EQ 55
- BASIC OPERATION OF THE EQ 55
- MENU SELECTIONS
- DISPLAY MODE MENU
- EXPANSION MENU
- GAIN MENU
- TRANSMIT POWER MENU
- CONFIGURATION MENU
- Configuration- Units of Measure
- Configuration - Background Color
- Configuration - Language
- Configuration - EXT I/F (External Interface) Sub-menu
- Configuration - EXT I/F - NMEA 0183
- Configuration - EXT I/F - Printer
- Configuration - EXT I/F - Ship's Speed
- Configuration - EXT I/F - Water Temperature
- Configuration - EXT I/F - Trigger
- Configuration - Test Pattern
- Configuration - TVG (Time Varying Gain)
- Configuration - Color Threshold
- Configuration - Scroll Speed
- Configuration - Alarms Sub-menu
- Configuration - Alarms - Set Min Depth (Set Minimum Depth)
- Configuration - Alarms - Set Max Depth (Set Maximum Depth)
- Configuration - Alarms - Min and Max Alarms ON/OFF
- Configuration - White Line
- Configuration - Filter
- Configuraiton - STC (Sensitivity Time Control)
- Configuration - Depth Adjust (Depth Adjustment)
- Configuration - Sound Velocity
- Configuration - Save Settings
- Configuration - Load Settings
- OPERATION OF THE EQ 55
- PART3.pdf
- PART4.pdf
- INSTALLATION INSTRUCTIONS FOR THE EQ 55.
- BASIC INFORMATION
- TRANSDUCERS AND SPEED/TEMPERATURE SENSORS
- DETERMINING THE POSITION FOR THE TRANSDUCER
- General
- Go Deep
- The Boundary Water Layer
- Propeller Noise
- Vessel Heave
- Noise From Protruding Objects on the Hull
- Summing up on Transducer Location
- Thru-hull Installation
- EQ 55 Standard Transducer Mounted to Wood or Fiberglass Hull
- EQ 55 Standard Transducer Mounted to Wood or Fiberglass Hull.
- Adapter plate for EQ 55 Standard Transducer Mounted to a Steel Hull.
- EQ 55 Standard Transducer Mounted to a Steel Hull.
- EQ 55 Standard Transducer Mounted to a Steel Hull.
- Steel Stuffing Tube for EQ 55 Standard Transducer.
- DISPLAY UNIT INSTALLATION
- ELECTRICAL CONNECTIONS
- Power Supply Connections
- Fuse
- Cabinet Grounding
- Rear Panel Receptacles
- Speed and Temperature Sensor Connections
- NMEA 0183 Interface Connections
- Color Printer Connection
- Location of Fuse and Rear Panel Receptacles
- Transducer Connectors ( European)
- Transducer Connectors ( North American )
- Speed Temperature Connectors
- NMEA Connectors
- MOUNTING BRACKET ASSEMBLY DRAWING
- OUTLINE & INSTALLATION DRAWING - EQ55 ECHO SOUNDER
- OUTLINE & INSTALLATION DRAWING - EQ55SA ECHO SOUNDER
- INSTALLATION INSTRUCTIONS FOR THE EQ 55.
- PART5.pdf
- PART6.pdf
- PART7.pdf
- PART8.pdf
- PARTA.pdf
- PARTB.pdf

950-70017001/Iss 1.2 EQ-55 Operators Manua
l
Page 3.8 Principles of Operation of an Echo Sounde
r
Kongsberg Simrad Mesotech Ltd.
Port Coquitlam, BC - Canada
3.4 CHOICE OF FREQUENCY
Your EQ-55 has two built-in frequencies. The lower frequency is most useful for
work in deep water. The high frequency will not usually be able to see as deep
as the lower frequency, but the higher frequency is best for seeing small targets
and greater detail. For example, looking for small bait fish is best done with the
high frequency. The operations section of this manual will show how to choose
the frequency displays you need. See Figure 3.7
Figure 3.7 - A representation of low frequency versus high frequency.
3.5 EFFECTS OF THE VESSEL'S SPEED
The display of fish on the EQ-55 depends directly on the vessel's speed, as well
as on the depth of the fish. When the vessel is at rest, the echo traces will
appear stretched out and flattened. As the vessel's speed becomes greater, the
echo traces will become shorter and more arched. The reason for this change in










