Raymarine e7, User Reference

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11.4 Dual / Single frequency fishfinder
Dual frequency operation allows the sonar to operate and display 2
frequencies simultaneously. If the preset mode that you are using
has two frequencies configured, you can view either one or both of
those frequencies in separate windows.
Selecting dual frequency view
From the fishfinder application:
1. Select Menu .
2. Select Select Preset .
3. Select Dual .
4. Select View .
5. Select the required setting:
• Frequency 1
• Frequency 2
• Both
11.5 Fishfinder preset configuration
Sonar frequency
The frequency of the sonar determines the width of the sonar beam,
the depth to which the signals will penetrate and the resolution
of the image. Each of the preset operating modes has its own
frequency settings.
The frequencies supported depend upon the DSM and transducer
in use on your system.
• Auto . When operating in automatic frequency the system will set
and adjust the frequency automatically to suit your transducer
and operating conditions.
• Lower frequencies (e.g. 50 kHz) produce a wide sonar beam
and penetrate the water well. A lower frequency provides a lower
resolution image that may not be as good at detecting small fish.
Use lower frequencies if you require a large coverage beneath
your vessel or if you are in deep water.
• Higher frequencies (e.g. 200 kHz) produce narrow beam
and produce a high resolution image. They are most useful in
shallower water (up to 1000 ft) and at higher speeds.
Setting the fishfinder frequency
With the Adjust Preset menu options you can:
• Configure one or two frequencies for each of the four presets.
• Select a display mode.
• Edit preset names.
• Reset presets to factory defaults.
1. From the fishfinder application select Menu .
2. Select Adjust Preset <mode> , where <mode> is the preset
already selected.
3. Select Configure Frequencies .
Using the fishfinder
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