Fish Schools, Sea surface fish | Furuno CSH-83, CSH-84 guide

Fish Schools

A fish school appears as a mass of echoes on the screen. The color of the mass shows the density of fish schools on the sonar beam. To find distribution and center point of a fish school, try several different tilt angles.

(A)Sea surface fish

Tilt angle: -5° to 10°

Fish school

Sea surface reflections

(B)Midwater, bottom fish Tilt angle: 30° or more

Fish echo which appears before seabed can be detected.

Seabed

Tilt angle: -0° to 20°

Fish echo which appears together with or after seabed can be detected.

Fish school

Seabed echo not displayed because of narrow tilt angle. Sea surface reflections are present.

Fish school

Large midwater fish school is present.

Seabed

When the tilt angle is shallow, the reflection echo from seabed is weak and the fish echo which appears from bottom

is easy to find.

Figure 11-2 Fish schools

11-2

Image 84

Furuno CSH-83, CSH-84 manual Fish Schools, Sea surface fish

Contents

Color Scanning Sonar 00080806600 Safety Instructions Do not use the equipment for other than its intended purpose Table of Contents PORT/STARBOARD, Horizontal Slice Displays Self Tests This page is intentionally left blank Features ForewordWord to CSH-83/84 Owners System Configuration Standard Option Control Layout on Display Unit and Remote Control Box Control Description Main Panel Main panel control description Control Function Sub Panel END Sub Panel 2 data setting window Signal AGCProcess 2AGC Alarm SonarUP/TM Sonrbeam Remote Control Box + + Turning the Power On/Off Adjusting Screen Brilliance, Control Panel BacklightingOperational Overview Lowering the Transducer Selecting a Display Mode Display mode description Setting the Tilt Angle Selecting a Display RangeSeabed echo and tilt angle How to discriminate fish echoes from the seabed Points to consider Tilt angle for surface fish Tilt angle and sea surface reflections Suitable tilt angle Tilt angle and beam coverage Adjusting the Gain Measuring Range and Bearing to a TargetPage Fine Tuning the Picture How to adjust TVGEliminating Unwanted Feeble Echoes Page AGC data setting window SIGNAL, Signal Pulselength data setting window TVGTX,PL2AGC data setting window SIGNAL, Signal Process Suppressing Seabed Tail Data setting window TVGTX, Output Rejecting Sonar Interference and NoiseIdentifying noise source Changing Tx cycle data setting window Tvgtx Cycle Adjusting Beamwidth Setting Noise limiter data setting window Signal Marks, Data and Display Mode Normal display modeMarks and Data Normal display mode w/text Echo sounder combination display Permanently Displayed Marks and Data History display Erasable Marks and Data Mark/Data Description Bearing marker Mark Description Range R Auto Tilt Auto Scan Gain Brill TVG TVG DIM Page Menu Overview User Menu Operation Menu screen location and display mode User Menu Hist DSP/GRPH User Menu Description Current VEC Save Picture System Menu Description FAR TVGTM DSP Target Lock BRG Readout Mark Size Menu Description Data SET Menu Description Color Curve Change Color NET Shoot PlanNET Sonde NET Plot Corr Init SET/TEST Menu Description Defaults Echo TestNET REC Others Event KEY Function Keys Programming the Function Keys Function Key Fine Tuning Replaying a Function Key Saving Function Key Settings to a Memory Card Replaying Function Key Settings from a Memory Card This page is intentionally left blank How to find fish school center Advanced Level OperationFinding Fish School Center Tracking a Fish School target lock Tracking a fish school Choosing target lock mode Target lock mark appearanceErasing target lock mark Tracking target lock mark Target lock and tilt angle Setting target lock conditions System Menu Target Lock Description of target lock items Detecting Fish Schools Aurally Fish Alarm How to set the fish alarm zone How to relocate fish schools Relocating Fish School for Easy Observation Comparing of Fish School Concentration Estimate marks and their data How to measure fish speed Measuring Fish School Speed Event Mark 10 Event marks Entering an event mark Erasing an event mark True Motion Display 12 True motion display Plotting Net Location Mark 13 Net location mark Observing Net Behavior 14 Net behavior Target Slice Display No. Display Information Applications This page is intentionally left blank PORT/STARBOARD, Horizontal Slice Displays Port/Starboard display Horizontal slice display Horizontal slice display Memory Card Operations Initializing Memory Cards Saving the Picture Transferring Echo Data from Internal Memory to Memory Card Net shooting data contents Saving Net Shooting DataHow net shooting data is saved Transferring net shooting data to memory card Deleting Memory Card Contents Replaying Saved Data Turning marks on/off through the data setting window Turning MARKS, Data ON/OFFTurning marks on/off through the user menu 10-2 Interpreting the Display Seabed Echoes Fish Schools Sea surface fish Sea Surface Reflections Wake False Echo by Sidelobe Noise and Interference Overvoltage Warning Unretracted Transducer Warning How to manually raise the transducer Self Tests Opening the Self Test Menu Self Test Description Single testContinuous test Panel test Color test Gray test SIO test Interface Unit CS-120A Self Test Interface unit CS-120A, cover opened 13-6 Input Data Selection Selection of Data at Interface Unit CS-120A Setting Distances Between Net Sonde Transmitters How to set net sonde transmitter distances Maintenance Display Unit Maintenance Hull Unit Maintenance Zinc block near the transducer must be replaced yearly Menu Tree User Menu Data SET Menu Init SET/TEST Menu System Menu Previous Page Specifications SP-1 Display SP-2 Hull Unit SP-3 SP-4 Index 11-2 IN-2