The purpose of this publication is to provide the descriptions and procedures required to allow for efficient use of the ST90 system. The manual does not contain detailed information about functions, dialog boxes and operating parameters.
By default, the display presentation covers the entire screen. The display presentation provided by the ST90 system consists of specific visual elements that work together. The visual elements provide you with the echo information you need, they help you to control the functionality needed to understand this information, and finally, they allow you to control the operational parameters.
During replay, the dedicated replay bar is shown immediately under the top bar. The replay bar allows you to retrieve saved files, and to control the playback.
Under normal use, the ST90 system presents several different echoes simultaneously. Some of these are clearly more interesting than others. It can be a challenging task to tell these echoes apart. It can also be hard to keep track of the different echoes as both echoes and your own vessel move. To ease the identification of these echoes you can use markers.
The phrase target is used to identify an echo in the display presentation that you wish to act upon.The echo may be from a material item, a shallow, reef or rock, or from fish, fish schools or mammals.In most cases, the target will move and continuously change its position relative to your own vessel.You must decide which echoes that shall be classified as targets, and whether you shall start manual or automatic target tracking. A position track permits the ST90 system to automatically control the tilt and bearing based on the movements of your vessel.
The Biomass information pane displays an index of the biomass in the in the current Inspection view. The biomass index is the sA value, or Nautical area scattering coefficient (NASC), measured with unit m2/nmi2.
The Size Distribution information pane presents a histogram with the echoes from single fish. The calculations are based on the fact that different fish species have different echo strength. The histogram presents the actual size of the fish by weight, length or echo strength (shown in dB).
The Fish Position information pane shows the position of the detected single fish echoes. The three circles in the information pane identify the operational frequencies. The echoes are seen from above. The colours indicate the echo strength.
The Zoom information pane allows you to magnify a chosen area of the current Inspection view.
The bottom bar is located at the bottom of the display presentation and stretches from the left side to the right side. The tabs on the bottom bar allow you to choose presentation mode.
The functions and dialog boxes provided in the ST90 user interface are not described in this publication.
The technical specifications summarize the main functional and operational characteristics of the ST90 system. They also provide information related to power requirements, physical properties and environmental conditions.
The ST90 system can send and receive information to and from several different peripherals. All transmissions take place as datagrams with data sentences. Each datagram has a defined format and length.
