Simrad Sonars

Simrad SX90 Long range high definition sonar system

Longer range with better resolution - same high resolution on all operative ranges. The Simrad SX90 is a low frequency, high-definition; long range sonar, designed for vessels where long detection range is important.

The combination of vertical and horizontal presentations show you the schools of fsh both from above and from the side at the same time. It is not necessary to go over the target to see the vertical distribution on the echo sounder.
When the beam stabilizer is activated, both the horizontal and vertical beams are electronically stabilized for roll and pitch. The full circle beam stays on the target independent of the vessel movement, even in rough seas.
The vertical slice is made “tippable”, and by selecting a 60° tip angle (or less), a full 180° coverage is obtained. The tip angle can be adjusted from +10 to -90°. This mode is ideal when you are trawling for fsh on deep water.

The Simrad SX90 sonar uses the ultimate of modern technology to detect targets under diffcult conditions.

90° Vertical Tip
This a new feature on our sonars. We transmit a narrow forward-looking fan-shaped 180° wide beam. The fan beam can be tilted from +10° and down to -90°. This feature is specially designed for pelagic trawlers.

20 to 30 kHz
The SX90 sonar can operate on 11 different frequencies from 20 to 30 kHz. Lower frequency give less absorption and wider beam for long range in deep water, where range is limited by salinity. The higher frequencies provide narrower beams for use in shallow waters were range is limited by reverberation. You will also avoid interference from other sonars in the area.

Narrow sound beams
Unlike other sonars, the SX90 both transmits and receives with narrow beams. Narrow beams are important in order to avoid false unwanted echoes from bottom and surface, this limits the detection range. At 30 kHz the transmit beam is only 6.7° wide. The receiver beam is only 7.4°.

Selectable beam width
With a narrow beam you continuously need to operate the tilt to keep the beam on the school. During the busy catching time, two wider vertical beams can automatically be selected. Target tracking is then made less dependent on the tilt angle.

Hyperbolic FM
This is another unique Simrad feature. The SX90 sonar transmits a long pulse with a continuously variable frequency. The receiver listens for an echo with the same frequency variations. Echoes with different frequency signatures are vastly reduced. The actual fsh echoes are enhanced, and fsh detection is made easier under diffcult conditions. Hyperbolic FM gives you 30 times better range resolution than common CW transmissions.

Large dynamic range
Picking the right school is important. Dynamic range means that you can tell the difference between a scattered school providing a weaker echo, and a dense school giving a stronger echo. Looking at the bottom echo, you can easily tell smooth from rough bottom. This is important when purse seining in shallow water, and during pelagic trawling where the footrope can touch the bottom.

Stabilized beams
The SX90 sonar is vertically stabilized evenly 360° around the ship, both for the horizontal as well as the vertical beams. The stabilized sonar beams enhance fsh detection in poor weather making searching still possible in situations you earlier gave up.

Dual mode
Conditions may sometimes change very quickly even within a few hours. With the dual mode feature you can set up two different sonar pictures on the monitor. One picture shows your normal settings, while the other is used to test new settings, flters, modes, pulse lengths, frequencies, tilt and other parameters in order to achieve better performance. If you fnd better setting, you save the new one settings as a new personal setting.

Store and Recall
The SX90 sonar can store display presentations manually or automatically, and you can recall these later for further studies. All the pictures in this document are screen captures from actual situations on the fshing grounds from vessels already using the SX90 sonar.

User settings
The sonar can store an unlimited number of user settings for different fishing conditions and different operators. Sonar settings are often personal, and most captains have favorite settings for different types of fishing, species, time of day etc. On the SX90 you can have your favorite settings stored and named just as you like.

Noise filter
The noise filter will suppress propeller noise, interference from other acoustic systems on your own vessel or on other vessels near by.