The Furuno CSH8LMK2 is a Full-Circle Scanning Sonar that rapidly detects fish schools, individual fish and changing underwater conditions. Fish distribution and seabed conditions are displayed in 16 colors, 360 degrees around the vessel. The unit took top honors in the Marine Specialty category in the 2021 National Marine Electronics Association (NMEA) awards.

The Sonar components consist of a standard 600mm (23.62”) stroke hull unit (400mm (15.75”) option available), a transceiver unit, and a processor unit. Operating at 85 KHz, the CSH8LMK2 is considered a mid- frequency Sonar. Its narrow beam width coupled with its enhanced target identification capabilities make it ideal for searching near the vessel or in shallow waters. Fish and bottom echoes are clearly separated and bait fish are more easily tracked. With automatic tilt scanning as a standard feature, the CSH8LMK2 is suitable for both midwater trawlers and purse seiners.

The Sonar's compact keyboard and Black Box configuration are designed to offer a flexible installation, and a variety of monitors are available to suit your installation and operational requirements. FURUNO's MU-series Marine Monitors are specially designed to meet the requirements of marine professionals around the world. For a second station, an additional display and a small remote controller can be simply plugged into the processor unit.

How it Works

The transducer arrangement consists of layers of elements. Each element is pointed in a slightly different direction which allows the Sonar to transmit 360 degrees simultaneously without rotating the transducer. The targets are redrawn on the display instantaneously according to the latest echo received from the transducer. Because this sonar scans quickly, it greatly improves the fishing operation, especially when searching for or following fast swimming fish.

On a 1,000’ (304.8 m)range Sonar updates the display 360 degrees every 0.54 seconds, while the conventional PPI sonar takes 32 seconds to train full circle under the same range/conditions. For the same range, Scanning sonars are capable of providing information that is about 60 times more comprehensive than PPI sonars. Faster target updating lessens the chance of missing a small change in underwater conditions. This is especially helpful when range and tilt require frequent adjustment while fishing, offering no frustration on redrawing time.

Control Unit

The control unit combines ergonomics and function in a user-friendly, comfortable configuration. All controls respond quickly to the operator’s command and the associated reaction can be seen on the screen immediately. Four user-defined functions can be assigned to Function keys (F1 to F4), providing for rapid setup and operation. An optional handheld remote controller allows for control of tilt, range and gain functions.

Display Types

Traditional Sonar

Navigation data can be displayed in the text window, with connection of appropriate sensors. The operator can place Event Marks on targets to better help tracking schools of fish or other objects of interest.

Sonar + Echo Sounder

The Sonar picture appears on the left and the signal fed from the Echo Sounder at the lower right side of the screen. This mode is suitable for judging fish school concentration.

Sonar Plus Audio

The Sonar picture appears on the left and the Audio display at the lower right side of the screen. This mode is useful for analyzing echoes in a desired area.

The CSH8LMK2 comes with everything needed for installation including a stainless-steel soundome shaft, a transceiver unit, a motion sensor with 10m (32.81 m) cable, a 5m (16.4 m) RGB video cable and all required hardware.

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