Simrad ST90

Long-range 14-24 kHz fish-finding omnidirectional sonar

The Simrad ST90 is a long-range and low-frequency fish-finding sonar with 360 degrees coverage. It is specifically designed for medium and large-sized fishing vessels, offering high performance with characteristics such as long-range capability, high resolution, narrow beams, and high source levels. The ST90 represents a no-compromise approach in sonar technology, aiming to be the ultimate in high-performance fish-finding. Utilizing lower frequencies than the SX90 and SU90 sonars, the ST90 embodies innovative developments made by Simrad in pursuit of unparalleled sonar performance.

If high performance is your number 1 criterion when choosing a sonar, such as long-range, high resolution, narrow beams and high source levels, the Simrad ST90 is your natural choice. We made no compromises during the design of the ST90. With the Simrad ST90, we use lower frequencies than the SX90 and SU90 sonars.

The centre operational frequency is 19 kHz, but you can select any operating frequency from 14 to 24 kHz in steps of 1 kHz. The cylindrical multi-element transducer allows the omnidirectional sonar beams to be tilted electronically from -10 to +84 degrees. These features will enable you to automatically track schools of fish and observe the whole water volume around the vessel.

It is common for sonars to require many pings to build the various views in the echo presentation. These sonars may, for example, need one ping to build the 360-degree omni view and then several other pings to fetch the echoes for the vertical views. On the ST90, all the sonar views in the presentation are built using the echoes from one single ping. This feature dramatically improves the update rate and provides better real-time information.

Superior sonar capabilities

The narrow beam opening angle of the ST90 (6.5° @ 17 kHz) in conjunction with the high source level makes it a formidable tool for high resolution, low-frequency sonar exploration. The advantages of these narrow beams include enhanced range and resolution and a vertical view that yields additional details for a clearer image. This sonar is especially advantageous when pinpointing fish near the seafloor or surface at extended distances. Furthermore, the beams reduce noise levels and mitigate bottom climbing, a common issue in wider beam sonars. Another noteworthy feature is the ability to construct all sonar views from a single ping, significantly improving the update rate and providing real-time information.

Advanced transducer design

Our goal was to make the ultimate high-performance fish-finding sonar. To achieve this task, we designed a completely new transducer. Each transducer element is larger than the SX90 and SU90 elements, but the number of elements is the same as the SU90. This high number of elements allows for the same narrow beam and a longer range. The ST90 has been designed to search with very long ranges in all weather and sea conditions. Whether it is heavy weather, hard bottom, open waters, or weak targets - all echoes are handled by the sonar due to the fully stabilized and very narrow beams combined with the cutting edge signal processing.

"Winson" operating software

This sonar uses the latest "Winson" operating software. This unique software platform is common for all Simrad sonars. It allows you to present the various sonar echoes in separate views, which you can move to separate display monitors. Another great feature of the new software is its ability to "ping" all the beams simultaneously. Multiple pings increase the ping rate and thus offer a more frequent update of the sonar echoes in the views.

Other standard features of the "Winson" operating software are:

  • User interface in more than 20 languages
  • Intuitive access to all operating parameters
  • Save and recall your favourite user settings
  • Save and replay sonar images and video sequences
  • Target and position tracking

Sonar operating panel

This sonar supports the optional Operating Panel Mk.2. This operating panel uses a handy multifunction joystick. The joystick facilitates tilt, vertical, and inspection beam control through simple pushes or twists of the knob. The operating panel communicates with the Processor Unit using an Ethernet connection. This communication format allows for advanced functionality. You can manage up to four different Simrad sonars using a single panel. Conversely, up to three panels in various locations on the vessel can operate a single sonar. The USB port on the operating panel also provides convenient software upgrades and user settings management. The operating panel also features dedicated and customizable buttons and knobs, and its design allows for a straightforward upgrade from older panels using a mounting bracket.

Seamless communication with other vessel sensors

The sonar system provides several standard interface lines. These interfaces ensure seamless communication with peripheral devices and sensors, with typical inputs like geographical information, vessel speed, and heading. The built-in motion sensor enhances operational accuracy, and you can increase this accuracy by adding an external motion reference unit (MRU).

Simrad support and sales

Kongsberg Discovery owns the Simrad brand name, which is your assurance of quality. All Simrad products are backed by Kongsberg Discovery's extensive worldwide support and training. On the Support pages, we have provided the relevant Simrad contact information for professional fish-finding systems for direct assistance.

Simrad provides a global sales organization for product information, software updates, and purchases.

We encourage you to stay in touch via our Instagram, Facebook, X (Twitter), and LinkedIn social media channels. 

System diagram

The Simrad ST90 system units are typically installed on the bridge and in a sonar room. The main communication line between the bridge units and the Transceiver Unit in the sonar room is a high-speed Ethernet cable. The Simrad ST90 fish-finding sonar comprises the following units:

(A) Display (the second display is optional)
(B) Processor Unit (computer)
(C) Operating panel (optional)
(D) Transceiver Unit
(E) Hull Unit
(F) Hoist motor
(G) Motor Control Unit
(H) Transducer

Current software version

We recommend always upgrading your Simrad ST90 system with the latest software version.

Contact your local dealer for an upgrade. They can provide the software update and relevant licenses and will install the software for you. Your dealer can also advise on using and maintaining your sonar system.

Latest software version

24.7.1

Articles and downloads

End-user documentation

Interactive Electronic Technical Manuals (IETM)

Download/open Simrad's product catalogue

Stay in touch with Simrad for product information and software updates

Find your local dealership

Our global dealership network enables distribution to more than 100 countries to meet customer needs at any location. Find your local dealership here.

We offer comprehensive after-sales assistance