Simrad released SN90 s.v.3.1.5

The Simrad SN90 Matrix Sonar for trawlers, purse seiners, and research applications has been updated with s.v.3.1.5 which is controlling all functionality, transmission and reception, interfaces with external peripherals, and sensors, and all user interface. It should be noted that a firmware update for the Transceiver Unit is not included with this SN90 software release.

This software update solves a number of software bugs that have been reported by SN90 users or detected during our own product testing. New functionality is also introduced. The following specific changes have been made:

Reducing bottom and surface reverberation with the RCG (Reverberation Controlled Gain) function

When you transmit an acoustic pulse into the water to search for a target, echoes will also be returned from any other objects in the beam. The energy reflected from these “unwanted” objects is referred to as reverberation. Reverberation is often a limiting factor, especially if you are searching for smaller targets. There are several types of reverberation:

  • Volume reverberation: The volume reverberation is caused by minute plankton and air-bubbles in the water. This reverberation has often daily cycles in intensity.
  • Surface reverberation: The surface reverberation depends on the weather condition and the waves.
  • Bottom reverberation: The bottom reverberation depends on the roughness and physical properties of the sea bottom.

The RCG (Reverberation Controlled Gain) controls the receiver processing. The algorithm handles each receiver beam individually. The filter reduces the unwanted echoes from the bottom and from the sea surface which is enhancing the visibility of schools. A rough guide to the settings can be used as a starting point for your own experiments, as follows:

  1. Use for scattered fish.
  2. Use for schools.
  3. Use for schools with higher density. This setting can also be used in horizontal views to detect schools close to the bottom.
  4. Use for scattered fish located close to the bottom. This setting uses a slightly different algorithm than the other scattered fish settings.
  5. Use for scattered fish located close to the bottom. This setting uses a slightly different algorithm than the other scattered fish settings.
  6. Use for scattered fish. This setting uses a slightly different algorithm than the other scattered fish settings.
  7. Use for scattered fish. This setting uses an algorithm dedicated to higher bandwidth.
  8. Use for schools. This setting uses an algorithm dedicated to higher bandwidth.
  9. Use for schools. This setting uses an algorithm dedicated to higher bandwidth.

Automatic adjustment of the echo presentations on wide display monitors

Wide displays are becoming more and more popular and the SN90 software supports up to two displays with an aspect ratio of 16:9 or 16:10. Recommended resolutions are 1920 x 1080 or 1920 x 1200, with minimum size 24” plus. The Longest Side Scaling feature is designed to take full advantage of the free space on a widescreen. The presentation is scaled up to fit the screen width. However, scaling up the views to an oblong shape means that a part of the presentation must be sacrificed. The echoes from behind your own vessel are therefore removed.

The noise filter has been improved

The Noise Filter is used to minimize the interference from other acoustics systems (sonars and echo sounders) on your own and/or other vessels. The filter also suppresses noise from your propellers, and from other similar noise sources. The Noise Filter is very effective if you are bothered by strong noise or interference, especially from your own vessel, or even from other vessels operating near you.

New presentation mode

The new presentation mode Horizontal is added. The mode contains one Horizontal view and one Inspection view. You can of course use the Docking Views function to place the views wherever you wish.

Specific bug fixes

  • The NMEACUR interface now handles relative direction correctly. In the previous releases, the values were always handled as true.
  • The panel backlight has been modified, when multiple sonars are connected to one control panel each one has to be set individually.

For further information you may contact the Official Distributor and Support Center for Greece:

Aegean Electronics SA

4 Zosimadon Str, Piraeus 185 31, Greece

Tel: +30 210 4123000

E-mail: info@aegeanel.com