* O M E 1 3 0 5 0 F 0 0 *

SAFETY INSTRUCTIONS

CAUTION

Do not exceed 18 knots when operating the equipment and do not exceed 16 knots when lowering or raising the transducer.

The transducer may become damaged.

The zinc block attached near the transducer must be replaced yearly.

The junction between the transducer and main shaft may corrode, which can result in loss of the transducer or water leakage inside the ship.

Do not use the equipment for other than its intended purpose.

Use of the equipment as a stepping stool, for example, may result in personal injury or equipment damage.

Replace the monitor when the picture becomes difficult to see.

The average life of the monitor is about 10 years. Replace it when the picture be- comes difficult to see, to protect vision.

A warning label is attached to the equip- ment. Do not remove the label. If the label becomes soiled or illegible, contact a FURUNO agent or dealer.

ii

TABLE OF CONTENTS

FOREWORD

CONTROL DESCRIPTION

OPERATIONAL OVERVIEW

FINE TUNING THE PICTURE

MARKS AND DATA

MENU OVERVIEW

iii

FUNCTION KEYS

ADVANCED LEVEL OPERATION

VERTICAL SCANNING DISPLAY

PORT/STARBOARD, HORIZONTAL SLICE DISPLAYS

MEMORY CARD OPERATIONS

iv

WARNINGS

SELF TESTS

INPUT DATA SELECTION

MAINTENANCE

v

System Configuration

viii

CONTROL DESCRIPTION

Control Layout on Display Unit and Remote Control Box

Figure 1-1 Display unit and remote control box

1-1

Main Panel

OFF ON

SCAN DEPTH

NET TARGET

COURSE LOCK

DIM CONT BRILL AUDIO

EVENT1 EVENT2

ESTI- ESTI-

MATE1 MATE2

Figure 1-2 Main panel

Main panel control description

1-2

1-3

Sub Panel 1

Figure 1-3 Sub panel 1

Sub panel 1 control description

1-4

Sub Panel 2 (data setting window)

SONR???BEAM

(Continued on next page)

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*2AGC and HOR functions cannot be used together. If one is used the other is automatically set to ???0???.

(Continued on next page)

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*HOR and 2AGC functions cannot be used together. If one is used the other is automatically set to ???0???.

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Remote Control Box

Figure 1-5 Remote control box

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OPERATIONAL OVERVIEW

Turning the Power On/Off

Turning the power on

Press the ON switch on the main panel. The lamp above the switch should light. If it doesn???t press the TX switch on sub panel 1.

Turning the power off

Retract the transducer with the cswitch and then press the OFF key on the main panel.

Note: The transducer is automatically retracted into the tank even if the OFF switch is pressed before retracting the transducer. However, make it a habit to retract the transducer before turning off the power.

Adjusting Screen Brilliance, Control Panel Backlighting

The BRILL control adjusts screen brilliance, and the DIM con- trol adjusts control panel backlighting. These controls are on the lower part of the main panel.

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Selecting a Display Mode

The CSH-23F/24F provides three display modes: normal sonar picture, echo sounder (E/S) combination, and history display combination. Those modes may be selected with the NORM, E/ S and HIST keys.

Table 2-1 Display mode description

HISTORY

2-2

Selecting a Display Range

Operate the RANGE control to select a display range. The range selected appears at the top center of the screen.

Setting the Tilt Angle

The tilt angle shows the direction to which the sound wave is emitted. When the sound wave is emitted horizontally, the tilt angle is said to be zero degrees and when emitted vertically, 90 degrees.

Finding a proper tilt angle is important when searching for fish.

Seabed echo and tilt angle

Case 1: Tilt angle 30 to 40 degrees

This tilt angle will display the entire seabed since it is captured by the full width of the beam.

Case 2: Tilt angle 10 to 20 degrees

This tilt angle will only display half the seabed since it is only captured by the lower half of the beam.

Case 3: Tilt angle 0 to 10 degrees

This tilt angle may or may not capture the seabed since the re- turning echo is weak.

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How to discriminate fish echoes from the seabed

The figure below illustrates how two fish schools aand b are displayed on the screen using three different tilt angles.

Case 1: Tilt angle 30 to 40 degrees. Fish school is obscured by the seabed.

Case 2: Tilt angle 10 to 20 degrees. Fish school is located above the seabed (midwater).

Case 3: Tilt angle 0 to 10 degrees. Fish school is located close to the seabed.

} Seabed

Figure 2-1 Fish echo and tilt angle

Points to consider

???Normally, a vertically distributed fish school is a better sonar target than the seabed, because it reflects the transmitted pulse back toward the transducer.

???In case 3, both fish schoolsa and b are presented. Gener- ally speaking, however, midwater fish schools tend to be larger than bottom fish schools and they are often displayed near the seabed on the display.

???It is difficult to detect bottom fish when they are not distrib- uted vertically.

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Tilt angle for surface fish

Sound emitted from the sonar transducer forms a circle-shaped beam with a width of approximately 12 degrees in the vertical direction (vertical beam width). The tilt angle is indicated by the angle between the center line of the beam and the horizontal plane. Then, if the tilt angle is set to 0 degrees, the center line is parallel with the sea surface and one half of the emitted sound goes upward, toward the sea surface.

This causes one half of the emitted sound to be reflected toward the transducer and displayed on the screen as sea surface reflec- tions. When the sea is calm, since the sound is reflected just like a light hitting a mirror at a narrow incident angle, it propagates away and the sea surface reflections become negligible.

However if the sea is not calm enough, they will become domi- nant and interfere with observation of wanted echoes. To mini- mize these sea surface reflections and to search surface fish schools effectively, the tilt angle is usually set between 5 and 6 degrees so the upper portion of the beam becomes almost paral- lel with the sea surface. When the sea is rough, it is often set to a little larger angle.

Tilt angle 5-6??

15??

Figure 2-2 Tilt angle and sea surface reflections

2-5

Suitable tilt angle

The figure below illustrates the relationship among tilt angle, depth and detection range. Refer to it to find out the suitable tilt angle for a given depth/detection range.

200 m

100 m

Figure 2-3 Tilt angle and beam coverage

2-6

Adjusting the Gain

The GAIN control adjusts receiver sensitivity (gain). Adjust it so fish echoes are clearly displayed with minimal noise on the screen. Too high a setting not only displays excess noise and makes it difficult to discriminate wanted echoes but also causes seabed echoes to be painted in strong colors, resulting in echoes being masked by seabed reflections. Normally, set the control somewhere between positions ???3??? and ???7???.

Figure 2-4 Gain settings and resulting picture

Measuring Range and Bearing to a Target

Operate the trackball to place the trackball mark on the target you want to measure the range and bearing. The range and bear- ing appear at the upper left corner on the screen.

??

????

B

Figure 2-5 Location of range and bearing indications

Note: The bearing is shown in either 360?? or 180?? indication relative to ship???s heading. In the latter case, bearing (???B???) is indicated as follows:

2-7

FINE TUNING THE PICTURE

Eliminating Unwanted Feeble Echoes

Echoes from targets such as seabed and fish return to the trans- ducer in order of distance to them, and when we compare their intensities at the transducer face, those from nearer targets are generally stronger when their reflecting properties are nearly equal. The sonar operator will be quite inconvenienced if these echoes are directly displayed on the screen, since he can not judge the actual size of the target from the size of echoes dis- played on the screen. To overcome this inconvenience, the TVG function is incorporated. It compensates for propagation loss of sound in water; amplification of echoes on short range is sup- pressed and gradually increased as range increases so that simi- lar targets are displayed in the similar intensities irrespective of the ranges to them.

The CSH-23F/24F has three TVG functions, NEAR, MEDIUM and FAR, and they mainly compensate for propagation loss on short, middle and long ranges respectively, centered at the ranges shown below. The higher the TVG setting the greater the ampli- fication of echoes.

Figure 3-1 Principle of TVG

The TVG is also used to suppress unwanted echoes and noise which appear in a certain range area on the screen such as sea surface reflections and cruising noise. To set TVG properly, do the following:

How to adjust TVG

1.Open sub panel 2.

2.Select TVG???TX.

3.Set TVG NEAR, MEDIUM and FAR to 5.

(These are the standard settings and you can maintain them in most cases.)

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4.When sea surface reflections or plankton layers disturb the picture, decrease appropriate TVG option by one or two steps by pressing ??? (minus) key.

5.When fish school is located on a long range setting (about 800 meters) which is approaching own ship.

Adjust the tilt to keep the fish school in the center of the sonar beam, namely, fish school is displayed in strongest colors possible. Confirm that the fish echo is displayed in the same color as it approaches. If the color suddenly changes to weaker colors as the fish enters MEDIUM and NEAR ar- eas, the TVG is improperly set. Adjust the TVG. If this again produces sea surface reflections and noise try to remove them with AGC and NL controls.

Note: If the above procedure does not produce satisfactory re- sults, the TVG curve can be changed on the SYSTEM menu. The 30 log setting is normal. The 25 log setting is useful for searching fish schools near shorelines or shallow waters. The 35 log or 40 log setting raises the gain on a long range and is suit- able for searching tuna, bonito, etc., which are usually searched with high gain setting.Ask for FURUNO dealer for detail.

3-2

Suppressing Seabed Tail

AGC (data setting window: SIGNAL, SIGNAL

PROCESS)

The AGC functions to automatically reduce the receiver gain only against strong echoes such as the seabed or a large fish school. Since weak echoes remain unaffected, a small fish school becomes easier to detect. Adjust it so that the AGC works only on seabed reflections. Do not set it too high; weak echoes may be missed.

Pulselength (data setting window: TVG???TX, PL)

The pulselength control determines the length of the transmis- sion pulse emitted into the water. While a longer pulse is advan- tageous for long range sounding, it has the disadvantage of being poor in discrimination of targets, that is, ability to separate sev- eral closely located targets. When searching bottom fish, there- fore, it is useful to shorten the pulselength in order to separate fish echoes from seabed reflections. Decrease the PULSELENGTH setting to shorten the pulselength. For search of surface and midwater fish in which seabed reflections are not so strong, use the longest pulselength ???9???.

2AGC (data setting window: SIGNAL, SIGNAL

PROCESS)

While it is ideal to suppress seabed echoes with the AGC con- trol alone there are some fishing grounds where this is not pos- sible. (The high power sonar has the advantage of long-range detection but this can also be a disadvantage, since weaker ech- oes may be hidden in strong, unwanted echoes such as the sea- bed.)

If you cannot suppress seabed echoes or sea surface reflections by the AGC control alone, use the 2AGC control. Normally a setting of 2 or 3 is suitable. For especially strong echoes, use a setting of 4 or 5.

AR, -4 to -1: Adjusts horizontal beamwidth. 2AGC function is fixed at ???3???.

0:2AGC function is off.

1 to 5: Larger the number, the greater the effect of 2AGC.

3-3

Suppressing Seabed and Sea Surface Reflections in

Shallow Waters

Data setting window: TVG???TX, OUTPUT

In shallow fishing grounds with hard or rocky bottom, seabed reflections often interfere with wanted fish echoes and they can not be eliminated sufficiently with the aforementioned TVG and AGC controls, especially when the TILT is set to a larger angle in order to track fish schools approaching within 400 m. In such cases try to reduce the output power by adjusting the OUTPUT control instead of turning down the gain. The picture becomes clearer when output power is reduced rather than when the GAIN is decreased as illustrated below.

CORRECT

METHOD

Fish echo

Reduce OUTPUT with GAIN kept constant

Figure 3-2 How to suppress seabed and sea surface reflections in shallow waters

Rejecting Sonar Interference and Noise

While observing the sonar picture, you may encounter occasional or intermittent noise and interference. These are mostly caused by on-board electronic equipment, engine or propeller noise, or electrical noise from other sonars being operated nearby.

Identifying noise source

To eliminate noise effectively, you should first identify the noise source as follows:

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1.Turn off the TX switch and operate all on-board equipment one by one while observing the picture.

2.Run the boat at various speeds to check if the noise is speed dependent.

If neither of the above two steps has effect on the picture, adjust one of the following:

Interference rejector (data setting window: SIGNAL,

SIGNAL PROCESS)

This control is similar to the interference rejector on echo sound- ers and radars. It is effective for rejecting random noise and sea surface reflections in rough sea conditions. Set it so that noise is just eliminated. Do not use an unnecessarily high setting since it may also reject small wanted echoes.

Changing Tx cycle (data setting window: TVG???TX,

CYCLE)

When other sonars operate nearby at the same transmission in- terval as that of own ship???s sonar, an interference ring caused by other sonars is displayed. To erase the interference ring from the screen, reduce the CYCLE on the data setting window.

Interference

Figure 3-3 How CYCLE works

Note: When the sonar is used in shallow water with the range set between 60 m and 200 m and Tx cycle at ???9???, seabed reflec- tions caused by the 2nd-to-the-last transmission may appear on near ranges. Reduce the Tx cycle setting to ???2??? or ???3??? to sup- press them.

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Setting F-shift (data setting window: SONR???BEAM,

SONAR)

If interference cannot be suppressed by the interference rejector (IR) or Tx cycle, change the setting of F-SHFT from 1 to 2.

Noise limiter (data setting window: SIGNAL, SIGNAL

PROCESS)

Weak, unwanted reflections, colored light-blue or green, appear when the water is dirty, plankton layers exists, or due to ship???s noise. The noise limiter (NL) can reduce the effects of these unwanted reflections???raising the setting causes them to become bluish to background color. Normally a setting of 3 or 4 is suffi- cient.

Adjusting Beamwidth

Beamwidth can be adjusted at SONR???BEAM, BEAM on the data setting window.

Table 3-1 Beamwidth adjustment menus

Set to "0" for normal use. The higher the setting the narrower the beam. This control may be used together with the AGC and NL controls to suppress sea surface reflections and seabed echoes.

HOR Note that when 2AGC function is on the horizontal beamwidth is adjusted at the 2AGC item on the data setting window. Settings AR and -4 to -1 adjust the beamwidth.

In order to reduce surface reflection VER controls upper part of the beam dents near own ship as shown the above.

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MARKS AND DATA

Marks, Data and Display Mode

Normal display mode

Figure 4-1 Marks and data appearing in the normal display mode

4-1

Normal display mode w/text

Figure 4-2 Marks and data appearing in the normal display mode w/text

Echo sounder combination display

Figure 4-3 Marks and data appearing in the echo sounder combination display mode

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History display

Figure 4-4 Marks and data appearing in the history display mode

Permanently Displayed Marks and Data

*Requires external sensor.

(Continued on next page)

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Erasable Marks and Data

(Continued on next page)

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N

W E

S

(Continued on next page)

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(Continued on next page)

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MENU OVERVIEW

Many functions are carried out through the menu system, which consists of the USER, SYSTEM, DATA SET and INITIAL SET/ DATA menus. The menu you will use most often is the USER menu.

Press MENU and ON together.

INIT SET/TEST (Press and hold down until the buzzer sounds.

All LEDs light while keys are held down.)

USER Menu Operation

The menu operating procedure is the same for all types of menus.

Below is the basic menu operating procedure for the USER menu.

1. Press the MENU key to open the USER menu.

USER MENU

Select item with dc[ \ keys and press MENU key.

Press END key to close menu.

Figure 5-1 USER menu

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2.Operate the arrow keys in sub panel 1 to select a menu. As you move through the menu, each item, initially shown as blue on gray, reverses to gray on blue to show selection. For example, select the HIST DSP/GRPH menu.

3.Press the MENU key to display menu selected.

Select item with dc[ \ keys and press MENU key.

Press END key to close menu.

Figure 5-2 HIST DSP/GRPH menu

4.Operate the up and down arrow keys in sub panel 1 to select menu item, and the right and left arrow keys to select option.

5.Press the END key to close the menu. Press the key again to display picture.

Note: The HELP key provides menu operating information.

Menu screen location and display mode

Menu screen location depends on display mode as shown in the figure below.

Menu

Menu

Figure 5-3 Menu screen location and display mode

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USER Menu Description

Table 5-1 User menu description

(Continued on next page)

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5-4

SYSTEM Menu Description

The SYSTEM menu can be displayed by pressing MENU and c together.

For help, press the HELP key.

(Continued on next page)

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(Continued on next page)

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DATA SET Menu Description

The DATA SET menu can be displayed by pressing MENU +

d . For help, press the HELP key.

0128 255

2. Color curve can be changed at colors no. 4, 8, 11, 13 and 15. Press up or down arrow key to set cursor on color no. you want to change curve.

3. Press the right or left arrow key to change value.

4. Press the MENU key to terminate color curve setting. Then, the display shown below appears. Follow the instructions on the screen.

Color curve setting is completed.

To save change and close the menu, press

MENU key.

To cancel change and close the menu, press

END key.

(Continued on next page)

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15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

2. Using the arrow keys, place the cursor on color segment you want to change color. If you are changing the color of marks or the menu, press the HELP key to display guidelines for changing their colors.

3. Press the up or down arrow key to

change value, between 0 and 100. You can press and hold down the key to get faster change.

4. Repeat steps 2 and 3 to change other colors.

5. Press END key to terminate color setting. Then, the display shown below appears. Follow the instructions on the screen.

Color curve setting is completed.

To save change and close the menu, press

MENU key.

To cancel change and close the menu, press

END key.

(Continued on next page)

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INIT SET/TEST Menu Description

The INIT SET/TEST menu can be displayed by pressing MENU and ON together.

(Continued on next page)

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5-12

FUNCTION KEYS

Similar to the quick dialing function on a telephone, the five function keys (F1???F3) on the main panel record control and menu settings and replay them back exactly as programmed. The items you can program are gain, display mode, TX ON/OFF, USER menu, SYSTEM menu, DATA SET menus and data setting win- dow. The function keys are useful for quickly setting up the so- nar for a specific purpose such as seabed detection.

Programming the Function Keys

1.Tune the sonar as desired.

2.Press the MENU key.

3.Select the FUNCTION KEY menu and press the MENU key.

Figure 6-1 FUNCTION KEY menu

4. Press the MENU key again.

6-1

Customized settings are registered to FUNCTION keys.

Select key number with??? ??? key and press MENU key.

Press END key to return to sub menu.

1

Figure 6-2 REGISTER menu

5.Press the up or down arrow key in the sub panel 1 to select the function key to program, then press the MENU key.

6.Press the END key several times to close the menu.

Replaying a Function Key

Press function key (F1???F3) desired.

Function Key Fine Tuning

The function key fine tuning keys ([+], [-]) let you fine tune the items shown in the table on the next page when a function key is active.

Note: Register function keys beforehand to use this function.

1.Press desired function key. The lamp above the function key pressed lights.

2.Press the [-] or [+] key as appropriate; the [-] key to lower the setting to de-emphasize echoes, and the [+] key to raise the setting to emphasize echoes.

The lamp above the [-] key lights when the setting is -1 to -4, and the lamp above the [+] key lights when the setting is 1-5.

6-2

Saving Function Key Settings to a Memory Card

1.Press the MENU key.

2.Select the CARD UTILITY menu.

Figure 6-2 CARD UTILITY menu

3. Select Save and press the MENU key.

Note: If the card has not been initialized, initialize the card by selecting Initialize and then save.

Replaying Function Key Settings from a Memory Card

Press the CARD REPLAY key on sub panel 1.

Note: When function key settings are replayed from a memory card, current settings on all function keys are erased. Therefore, if necessary, save current function key settings to another memory card before replaying.

6-3

ADVANCED LEVEL OPERATION

Finding Fish School Center

When you want to find the center depth of a fish school, use the auto tilt function, which automatically scans the tilt angle within the selected width. There are two automatic scan range, WIDE and NARROW, which can be selected by the INIT SET/TEST menu. Note that the NARROW is under develepment.

Table 7-1 Automatic scan range at menu setting WIDE of

OTHER/INIT SET/TEST menu

For example, when the RANGE control, TILT lever and WIDTH key are set to 800 m, 8?? and width (1), respectively, the tilt angle varies at every transmission as follows:

8?????8?????10?????10?????12?????12?????14?????14?????12?????12?????10?????10????? 8?? ???8????? 6?????6?????4?????4?????2?????2?????4?????4?????6?????6?????8?????

8??

Figure 7-1 Tilt angle setting

Table 7-2 Automatic scan range at menu setting NARROW of

OTHER/INIT SET/TEST menu

7-1

Tracking a Fish School (target lock)

Target lock, which requires speed and heading inputs, automati- cally tracks an important fish school so that you won??t lose sight of it on the display screen. Two types of target lock are avail- able: Target Mark or Fish. One may be selected on the SYS- TEM menu.

Tracking a fish school

1.Operate the trackball to place the trackball mark on fish school you want to track.

2.Press the [TARGET LOCK] key to light the lamp above it. The target lock mark ( . ) appears on the fish school and tracking begins.

ABCD

60?? 60??

Depth

Figure 7-2 Target lock mark and target lock data

Note 1: Range offset is applied to both ship??s movement and fish school movement on the screen. Tilt angle is not offset.

Note 2: When the target goes out of the tilt angle range the lamp above the [TARGET LOCK] key blinks, and then target lock is cancelled.

3. To cancel target lock, press the [TARGET LOCK] key again.

7-2

Target lock mark appearance

The size and thickness of the target lock mark indicates fish speed and tracking status, as shown below.

(More than 5 Mark thickness shows Tx cycles) tracking status.

(Up to 3 Tx cycles)

Figure 7-3 Target lock mark appearance

Erasing target lock mark

Target lock marks may be erased as follows:

1.Open the sub panel 2.

2.Select DELETE MK.

3.Press the [+] key for DELETE MARK FISH.

Choosing target lock mode

Two types of target lock are available: target mark and fish.

Target mark: Tracks the target lock mark, changing range and tilt angle according to ship???s movement. The fish school itself is not tracked.

Fish tracking: Tracks fish school??s horizontal movement, chang- ing range and tilt to track movement.

Do the following to select target lock type:

1.Open the sub panel 1.

2.Press the [MENU] key while pressing the up arrow key in sub panel 1 to display the SYSTEM menu.

3.Select TARGET LOCK, and then press the [MENU] key.

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4.Select Tracking Method, and then press the [MENU] key.

5.Select method desired.

6.Press the [END] key several times to close the menu.

Tracking target lock mark

1.Operate the trackball to place the trackball mark on the fish school you want to track.

2.Press the [TARGET LOCK] key to light the lamp above it.

The target lock mark ( ) appears on the fish school and tracking begins.

Tilt angle is automatically changed to keep the target lock mark location within the sonar beam.

3. To stop tracking, press the [TARGET LOCK] key again.

Note 1: If the target goes out of the picture or the tilt angle is greater than 60 degrees the lamp above the [TARGET LOCK] key flashes to call your attention.

Note 2: Target lock position and data are calculated according to tilt angle.

Note 3: The bearing mark moves to the target lock mark loca- tion when target lock becomes active. Bearing to the target lock mark is shown.

Note 4: Target lock is temporarily disabled when the distance to the tracked fish school is less then 40 m. It is resumed once the distance becomes more than 40 m.

Note 5: The target lock works up to a tilt angle of 60 degrees. In the drawing below, the tilt angle is fixed at 60 degrees between B and C. During this period, however, calculation is continu- ously being performed. When own ship comes to point C, target lock is resumed.

ABCD

60?? 60??

Depth

Figure 7-4 Target lock and tilt angle

7-4

Setting target lock conditions

1.Open the sub panel 1.

2.Press the [MENU] key while pressing and holding down the down arrow key in sub panel 1.

3.Select TARGET LOCK with the arrow keys.

4.Press the [MENU] key.

Select item with ??? ??? ??? ??? keys and press MENU key.

Press END key to close menu.

Figure 7-5 Target lock menu

5.Press the up or down arrow key to choose item; right or left arrow key to set option.

6.Press the [END] key several times to close the menu.

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Description of target lock items

TrackingMethod

Sets target lock function: target lock mark, fish or automatic.

Track Echo Color

Sets minimum echo signal level to track. A fish school whose signal level is above the level set here is tracked.

Fish Speed Limit

Sets fish speed at which target lock is cancelled.

Fish Track Window

Set distance at which to track fish school??s track when it exits the tracking window.

Fish Speed Update

Selects update interval of fish speed readout; 5,10, 20 or 30 sec- onds.

Target Lock Window

Sets size of target lock window. The window itself is not show on the display.

NORMAL: 32 x 32

LARGE: 64 x 64

LARGEST: 128 x 128

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Detecting Fish Schools Aurally

Sometimes you may be preoccupied with other tasks and unable to concentrate on watching the sonar picture. In such cases it would be a good choice to use the audio function. This function enables you to monitor echoes from fish schools and seabed through the built-in speaker.

After you???ve become accustomed to monitoring fish aurally, you should be able to detect a fish school from a range longer than you can detect it on the screen. In addition you may judge whether the fish school is approaching or going away; the tone becomes higher when the school is approaching and lowers when the school is going away.

1.Operate the trackball to place the trackball mark to the direc- tion you want to monitor through the speaker.

2.Press the R/B key. The bearing mark appears on the display. Echoes in a 30?? , 60?? , 90?? , 180?? or 330?? sector centering the bearing mark are monitored through the speaker. You can adjust speaker volume with the AUDIO control.

3.To change coverage area, open the data setting window (sub panel 2) and change width of AUDIO SECTOR.

4.To scan the coverage area, open the data setting window, turn on AUTO SCAN and set scanning WIDTH.

Note: You can display the signal monitored through the loud- speaker on the history display combination window by pressing the HIST key, if AUDIO is selected on the HIST Window DSP menu in the USER menu.

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The Fish Alarm

The fish alarm sounds an audible alarm when a fish echo above a preset strength enters an alarm zone. You set parameters for the fish alarm at ALM on the data setting window.

ON/OFF: Turn alarm on or off.

1.Open the data setting window and select ALM???AUDIO.

2.Press the + key of the ZONE item.

3.Operate the trackball to place the trackball mark on the start- ing point of the alarm zone.

4.Press the + key.

5.Rotate trackball clockwise to select the end point. The dis- play paints a fan-shaped alarm zone.

6.Press the + key.

Starting

point

Alarm zone

End point

Figure 7-6 How to set the fish alarm zone

Note: There must be at least three degrees difference between the starting and end points to get a fan-shaped alarm zone as shown in (a) and (b). Otherwise, the unit paints a 360 degree alarm zone as in (c) and (d).

7-8

Relocating Fish School for Easy Observation

1.Operate the trackball to place the trackball mark on the posi- tion where you want to relocate the own ship mark.

2.Press the OFF-CENT key.

3.To move the own ship mark back to the screen center, press the OFF-CENT key again.

Fish

Press theschool

OFF-CENT key.

Own ship mark

Place trackball mark here,

Figure 7-7 How to relocate fish schools

7-9

Comparing of Fish School Concentration

You can get an estimate of the volume of two fish schools by using the two ESTIMATE keys.

1.Operate the trackball to place the trackball mark on a fish school, and then press the ESTIMATE 1 key.

The estimate mark appears on the fish school. Relative vol- ume is shown by a figure between 0 and 100, below the es- timate mark. When inside the mark is filled with reddish brown, volume figure is ???100???.

2.Operate the trackball to place the trackball mark on another fish school and press the ESTIMATE 2 key.

3.Compare estimate figures for each fish school.

4.To turn off the estimate marks press their respective keys.

Figure 7-8 Estimate marks and their data

7-10

Measuring Fish School Speed

To ensure a good haul, it is important to estimate the direction and speed of the fish school before shooting the net. You can do this with the FISH key. If the tidal current data is used together with fish speed data, you can determine the timing of the net shooting more efficiently. This function requires speed and head- ing inputs.

1.Place the trackball mark on the center of a fish school, and

then press the FISH key. The latest fish mark () appears on the fish school.

2.Wait 1 to 2 minutes.

3.Place the trackball mark on the same fish school selected in

step 1 and press the FISH key. The latest fish mark () ap- pears on the target and the 2nd latest fish mark () appears on the location selected at step 1. At the bottom left corner of the screen, the distance between the two fish marks, and fish school course and speed appear.

4.If you want to delete fish marks and fish speed marks, open data setting window, select DELETE MK and then press the FISH key.

Figure 7-9 How to measure fish speed

Note 1: Movement is calculated using ship???s speed and bearing inputs. Accordingly, pitching and rolling may affect the calcula- tion. For better results, try the procedure two or three times to verify reliability.

Note 2: The time and distance between pressings of the FISH key should be as long as possible to increase accuracy of mea- surement. For more accurate measurement repeat the procedure two or three times.

7-11

Note 3: Each time the FISH key is pressed the latest fish mark and ship???s speed mark change in the sequence shown below:

Fish key pressed once:

The Event Mark

The event mark is useful for finding the horizontal range, depth and bearing to a location some distance from current position. This function requires speed and heading inputs.

There are two types of event marks: event mark 1 and event mark 2. 10 of each type of mark can be displayed. The unit marks the latest one by () for event mark 1 and by () for event mark 2. Older event marks are displayed by a cross plus event number (event mark 1) or an inverted Y with event number (event mark 2). When you enter more than ten event marks, the unit erases the oldest mark, one by one.

Latest

Figure 7-10 Event marks

7-12

Entering an event mark

1.Set the trackball mark where you want to place an event mark (latest event mark).

2.Press an EVENT key. The horizontal range, depth and bear- ing to the event mark appear at the bottom left corner of the screen.

??? 234: Horizontal range (m) from own ship mark

??? 19: Present depth (m) to mark

(35): Depth (m) of mark at moment EVENT key is pressed.

B265: Present bearing (degree)

Bottom left-hand corner of screen

Figure 7-11 Event mark description

Plotting an event mark on the display is equivalent to dropping a buoy with an anchoring chain that extends from surface to bot- tom. The buoy is fixed at its present geographical location, but the marker on the display moves to a point where present beam plane intersects the anchor chain of the buoy as the ship moves or the tilt angle is changed. This can be said of other marks as well such as fish mark and trackball mark.

Erasing an event mark

Open the data setting window (sub panel 2) and select DELETE MK. Press appropriate EVENT key to erase mark.

7-13

True Motion Display

The relative motion display places the own ship mark at the screen center, and echoes from fish and the seabed move on the screen relative to own ship???s movement. This means that even when the ship is dead in water, fish echoes move on the display.

In the true motion display, however, stationary objects are fixed and own ship and fish echoes move on the display in accordance with their true courses and speeds. Thus you can observe own ship and fish echo movement with respect to the seabed.

Open the data setting window and select SONR???BEAM. Set UP/ TM in the SONAR menu to TM. This function requires speed and heading inputs.

Although the true motion mode is available for use in all modes, use in the combination mode is not recommended since the own ship mark may move into the combination picture area.

Figure 7-12 True motion display

7-14

Plotting Net Location Mark

Before shooting net, you will decide the shoot timing consider- ing the water current direction, distance to fish school and mov- ing direction of the fish school. Use the net location mark as a guide to decide the timing.

This function requires speed and heading inputs.

1.Place the trackball mark on fish school to be caught.

2.Press the NET COURSE key. The net location mark is de- picted by dotted ring with a diameter equivalent to that of your purse seine net, being centered on the trackball mark.

Trackball mark

Net location mark

Figure 7-13 Net location mark

3.To adjust the location of net location mark, move the trackball mark.

4.When the location is finalized, press the NET COURSE key again. The dotted ring is replaced by solid ring and the lamp above the NET COURSE key lights.

5.To erase the mark, press the NET COURSE key again.

You can adjust the diameter of the net location mark on NET

SHOOT PLAN in the DATA SET menu.

7-15

Observing Net Behavior

With net sonde connection you can observe net behavior after the throwing of the net, on the echo sounder combination mode. Accurate depiction of net sonde position depends on proper set- ting of the distances between net sonde transmitters. You can set those distances on NET SONDE XMTR in the DATA SET menu.

This function requires speed and heading inputs.

1.Press the SHOOT key just upon throwing the net into the water.

Then, the net shooting mark () appears at the own ship mark and also at the right edge of the echo sounder picture. Afterwards, whenever a net sonde transmitter on the net is thrown into water, a net sonde mark appears on own ship mark and moves with ship movement. The depths of net sonde transmitter units are digitally displayed at the lower left of the screen after the receiving transducer is placed into water. The net sonde marks appear also on the echo sounder picture as below, where the length of vertical line shows the depth of the net sonde transmitter unit.

2.To erase net sonde mark and associated data, press the SHOOT key again.

Figure 7-14 Net behavior

7-16

Target Slice Display

Using automatic tilting, the target slice mode displays the echo inside the estimate mark at several different tilt angles (depth). To access the target slice display, press the TARGET SLICE key. The table and illustration below describe the target slice mode.

Figure 7-15 Target slice display

7-17

VERTICAL SCANNING DISPLAY

The vertical scanning display provides a wide fish eye view of underwater conditions from the surface to the seabed. The fig- ure below illustrates the concept of the vertical scanning mode, in comparison with the normal sonar beam. The vertical scan- ning mode helps you keep fast moving fish such as bonito and tuna within the sonar beam.

Figure 8-1 The concept of the vertical scanning mode

Using Vertical Scanning Display

1.Press the VERT SCAN key on the main panel. The lamp above the switch lights, indicat- ing that the vertical scanning function is ON.

2.Press the TILT/SCAN lever to set a scan- ning depth. Your selection appears at the upper right-hand corner of the display like ???D120M???. Select a scanning depth which does not display the seabed, so you won???t hide any echoes in the seabed. When the seabed is hard and rocky, it may appear even if may appear even if the scanning depth is set shallower than the seabed depth. In such case, set the scanning depth further shallower.

3.To suppress sea surface reflections, open the data setting window and set the VER BEAM in the SONR???BEAM item to other than 0. Upper part of the beam dents as shown at right.

4.To escape from the vertical scanning mode, press the VERT SCAN key.

Figure 8-2 Vertical scanning

8-1

Display Indications

Figure 8-3 Indications of vertical scanning display

Application to Bonito and Tuna Fishing

Tracking of bonito and tuna presents a special challenge to the sonar operator: He must try to keep them within the sonar beam, a formidable task considering their high speed and penchant for leaping and diving. The CSH-23F/24F, however, with its wide vertical scanning beam, makes this task easier.

Searching

Neither the naked eye nor binoculars can continually track fish schools which make lightning quick runs between the surface and midwater. A sonar, however, provides a continuous view of several hundred meters of sea area around the boat, both at the surface and below it.

8-2

Tracking

If you are visually tracking a fish school which characteristi- cally leaps and dives regularly, or a school with a flock of birds hovering over it, the school will scatter once the vessel ap- proaches, thus you will lose sight of the school. The CSH-23F/ 24F provides continuous pictures of underwater conditions, so you can always know where a fish school is. For tracking the schools which leap and dive often the vertical scanning mode is especially effective.

Figure 8-4 Tracking

Approaching

???The sonar lets you view fish school movement continuously, thus you can approach a school confident of a good catch.

???While a flock of birds hovering over the sea surface is usu- ally a good indication of the presence of a fish school, the sonar can better verify fish school size.

Figure 8-5 Approaching

8-3

Catching

While the sonar operator monitors the sonar for other fish schools, the crew can scatter bait and water to attract fish to the boat.

Figure 8-6 Catching

8-4

PORT/STARBOARD, HORIZONTAL SLICE

DISPLAYS

The port/starboard display or horizontal slice display may be displayed by pressing the [HIST] key. The display shown de- pends on the setting of ???HIST DSP/GRPH??? in the USER menu.

Port/Starboard display

The port/starboard display takes echoes along the bearing (port, starboard) selected on the SYSTEM menu and displays them on the lower 1/3 of the screen. If the bearing width is set to 90 degrees, for example, the CSH-23F/24F displays echoes in both port and starboard directions. The picture is scrolled vertically to downward.

APort/starboard sampling angle can be set between 0 and 180 degrees. Setting sequence: SYSTEM menu, HIST DISPLAY, PRT/STBD Sample.

BFixed at 6 degrees.

Figure 9-1 Port/starboard display

9-1

Horizontal slice display

120 degrees of the picture in the horizontal direction is shown for a given depth (D) in the horizontal slice window at the bot- tom of the display. The area to display may be selected with the [R/B] key.

Figure 9-2 Horizontal slice display

1.In the normal display, place the trackball mark on the echo you want to see displayed in the horizontal display, then press the [R/B] key.

The horizontal slice marker, 120?? in width and centered on the bearing mark, appears on the display. Echoes within the marker appear in the window at the bottom of the display, scrolling leftward.

2.Place the trackball mark in the horizontal slice window to find data. The trackball mark changes to the cross cursor. Range and depth to the cross cursor are shown.

Note 1: Picture advancement is synchronized with ship???s speed. The picture does not advance when the ship is dead in water or there is no speed input.

Note 2: The width of the horizontal slice marker may be changed on the SYSTEM menu with H-Slice Width.

9-2

MEMORY CARD OPERATIONS

Initializing Memory Cards

Before you save information to a memory card it must be initial- ized (formatted).

1.Press the MENU key to display the USER menu.

2.Select the CARD UTILITY menu.

3.Select Initialize. It takes more than two minutes to initialize a memory card.

4.Press the END key a few times to display the user menu.

The memory card stores 256k bytes of data. This is equivalent to about two picture screens or about 20 pictures of echoes in- side the estimate mark. The following data are automatically saved as system data when the memory card is initialized: panel setting, function key settings, and menu settings.

10-1

Saving the Picture

You can save either the whole screen or the echo inside the esti- mate mark to the internal memory or a memory card.

1.Press the MENU key to display the USER menu.

2.Select SAVE PICTURE.

3.Select item to save:

Whole: Saves whole picture to memory card.

Est MK: Saves echo inside the estimate mark to internal memory. (About 20 pictures can be saved.)

QK Save: Saves whole screen to the internal memory. (One picture can be saved.)

4.Press the END key to close the USER menu.

5.Press the MEMO key on the main panel.

It takes about two minutes to save a whole screen to a memory card. During this time the normal picture is displayed but the unit accepts no key input.

Transferring Echo Data from Internal Memory to Memory Card

1.Press the MENU key to display the USER menu.

2.Press arrow keys to select CARD ECHO DAT.

3.The display shows all inside-estimate mark pictures stored in the internal memory. Using the arrow keys select picture to save to memory card.

4.Press the MENU key. The lamp to the right of the memory card drive lights while picture data is being saved.

5.Press the END key several times to return to the USER menu.

10-2

Saving Net Shooting Data

How net shooting data is saved

The unit starts accumulating net shooting data when the SHOOT key is pressed. When net shooting is concluded by pressing the SHOOT key again, the echo inside the estimate mark and other net shooting data are saved to the internal memory. Note how- ever that if ship???s movement between pressings of the SHOOT key is less than 1/3 of the net length the unit judges that net shooting is suspended and does not save net shooting data.

Transferring net shooting data to memory card

1.Press the MENU key.

2.Press arrow keys to select CARD NET DATA and press the MENU key.

3.If desired, according to on-screen instructions, select fish species to be added to net shooting data as a comment, and then press the MENU key.

4.If desired, enter fish quantity estimate by:

a)selecting number with up or down arrow key

b)selecting place with right or left arrow key

c)registering value by pressing the MENU key.

Net shooting data contents

Net shooting data is comprised of the following:

???Echoes inside estimate mark (the ones which are displayed the first time the SHOOT key is pressed)

???Ship???s position, date, time

???Ship???s track, net movement, current direction, water depth and/or water temperature

???Net sonde mark

10-3

Replaying Saved Data

Whole picture or echo inside estimate mark

1.Press the RECALL key (on the main panel).

2.Press the right or left arrow key in sub panel 1 to select item to replay. The left arrow key selects older data (for example, data in memory card); the right arrow key newer (for ex- ample, data in internal memory).

3.After viewing picture, press the RECALL key to escape.

Note that the priority order for replay of echo inside estimate mark is internal memory-saved picture followed by memory card contents.

Net shooting data

1.Press the NET REPLAY key (on sub panel 1).

2.At the screen bottom, comments are listed. Select the item to replay.

3.After viewing the data, press the NET REPLAY key again to escape.

Deleting Memory Card Contents

You can delete unnecessary data from a memory card.

1.Press the MENU key to display the USER menu.

2.Select the CARD UTILITY menu followed by the MENU key.

3.Select the DELETE and press the MENU key. The card con- tents are listed at the screen bottom.

4.Select data to delete.

5.Press the MENU key.

6.Press the END key a few times to close the menu.

10-4

TURNING MARKS, DATA ON/OFF

You can turn marks and data on or off through the data setting window or the USER menu.

Turning marks on/off through the data setting window

Select DELETE MK to delete the following marks:

Turning marks on/off through the user menu

The following marks can be turned on/off through the USER menu:

11-1

INTERPRETING THE DISPLAY

Seabed Echoes

When the tilt angle is widened, the seabed echo illustrated be- low will appear on the display. When the tilt is narrowed, the seabed trace becomes wider and weaker. By observing the sea- bed condition on the display, the skipper can prevent net dam- age.

Figure 12-1 Seabed echoes

12-1

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.

Figure 12-2 Fish schools

12-2

Sea Surface Reflections

To reduce sea surface reflections, set the tilt angle to 5?? or higher, so the upper edge of the sonar beam does not hit the sea surface, or adjust TVG. When a narrow tilt angle is used, sea surface reflections cover a large area as illustrated below.

Figure 12-3 Sea surface reflections

Wake

A wake produced by own ship or another ship can be a strong reflecting object when a narrow tilt angle is used. As the wake appears as a thick continuous line, it can be easily distinguished from a fish school. A wake contains many air bubbles which attenuate ultrasonic energy, making it difficult to sound beyond the wake.

Other ship

Own ship

Own ship's screw noise

Figure 12-4 Wake appearance on the display

12-3

False Echo by Sidelobe

An ultrasonic wave is emitted only in the direction set by the TILT lever, however there are some emissions outside the main beam. These are called sidelobes. The energy of the sidelobe is fairly weak but when the water is comparatively shallow and the bottom is rocky and hard, strong signals are detected by the sidelobe. These are represented on the display as a false echo as shown below.

The seabed echo detected by sidelobe appears at a certain tilt angle when the sidelobe points vertically.

Figure 12-5 Sidelobe echoes

Noise and Interference

Interference from a sonar on another ship appears on the screen as shown in (A) below. This interference can be suppressed by changing the CYCLE setting in TVG???TX on the data setting window. Interference from electrical equipment on board own ship appears as shown in (B) below. Noise from marine life ap- pears on the display as shown in (C). Electrical interference and marine life noise can be suppressed with IR on the SIGNAL menu in the data setting window.

Figure 12-6 Noise and interference

12-4

WARNINGS

Overvoltage Warning

If the input voltage to this unit rises above 125 VAC, the over- voltage detection circuit activates, an alarm sounds and the mes- sage OVERVOLTAGE appears at the screen center.

If this occurs, retract the transducer, turn the power off and check the ship???s mains voltage. It should be about 100 VAC.

Unretracted Transducer Warning

If the transducer is not completely retracted within 30 seconds after pressing c, an alarm sounds and the message XDCR NOT RETRACTED! appears at the screen center.

If this occurs, do the following:

1.The power cannot be turned off because the transducer can- not be retracted. Turn off the main breaker for the display and power supply units to stop operation.

2.Confirm that the net is not tangled in the transducer.

3.Confirm that the breaker inside the raise/lower control box (mounted on the hull unit) is on.

4.Remove the cover of the raise/lower control box. Push the (Red) reset button to reset the raise/lower control box.

5.Turn on the power and press cto retract the transducer into the tank. If it does not retract, the main shaft of the hull unit may be bent. Turn off the power and manually raise the trans- ducer up to the highest position by using the hand crank. (See the illustration on the next page.)

13-1

Reset Button

Breaker

Main Shaft

Raise/Lower Control Box

Hand Crank

Hull Unit

Figure 13-1 How to manually raise the transducer

13-2

SELF TESTS

The CSH-23F/24F has various self tests to check it for proper operation. If a test reveals equipment malfunction do not attempt to check inside the equipment. There are no user serviceable parts inside the equipment.

WARNING

Do not open the cover.

There are no user-serviceable parts inside. Refer any repair work to a qualified technician.

Opening the Self Test Menu

1.Turn on the power while pressing and holding down the MENU key.

2.Press arrow keys to select SELF TEST.

INIT/SET MENU SELF TEST

Select item with dc keys and press MENU key.

Single Execute

Continuous Execute

Panel Execute

Color Execute

Gray Execute

SIO Execute

Figure 14-1 SELF test menu

3.Press up or down arrow key to select test desired.

4.Press the MENU key to start test.

14-1

Note: Above program numbers are for

CSH-23F.

Figure 14-2 Single test

Continuous test

14-2

14-3

Figure 14-6 Gray test

Figure 14-7 SIO test

14-4

Interface Unit CS-120A Self Test

1.Open the cover of the interface unit.

2.Find DIP switch DP-1 on the lone circuit board. Turn switch #6 on to start the self test. The results of the check appear on the digital display beside the DIP switch.

3.Turn the DIP switch off after completion of the test.

, , , , , , , , , ,

, , , , , .

Figure 14-8 Interface unit CS-120A, cover opened

14-5

INPUT DATA SELECTION

Selection of Data at Interface Unit CS-120A

Figure 15-1 DIP switch settings in the interface unit

15-1

Setting Distances Between Net Sonde Transmitters

To accurately display the net shooting mark and net sonde mark position, the distance between transmitters must be correctly set. This is done on the DATA SET menu.

R0

Figure 15-2 How to measure distances between transmitters

How to set net sonde transmitter distances

1. Press the MENU key while pressing and holding down d . The DATA SET menu appears.

Figure 15-3 DATA SET menu

2.Select NET SONDE and then ???Net Sonde XMTR.

3.Enter number of net sonde transmitters and distances between them.

15-2

MAINTENANCE

WARNING

Do not open the cover.

There are no user-serviceable parts inside. Refer any repair work to a qualified technician.

Display Unit Maintenance

Handle the equipment with care.

Damage can cause corrosion.

Magnets or magnetic material can can distort the picture.

16-1

Hull Unit Maintenance

16-2

MENU TREE

A-1

DATA SET Menu

A-2

INIT SET/TEST Menu

A-3

A-4

A-5

SPECIFICATIONS

1. GENERAL

(1) Range, TX Cycle, Pulselength

NOTE

1)Transmission cycle is selectable in 10 steps.

2)External keying pulse can be used as a trigger.

3)Maximum range scale does not mean maximum range.

Detection capability depends on nature of fish school and sea condition.

SP-1

2. DISPLAY

bearing), Fish mark data (distance moved*, direction* and speed* between two latest fish marks), Estimate mark data (estimation of fish volume by echo strength), Net shooting data (time and distance run* between turning on and off of net shooting mark), Setting change data (new setting ap- pears in larger characters for 5 seconds when changed), Current data* (current speed, direction, layer, depth),

SP-2

Navigation data *(ship???s speed, heading, water depth, water temperature), Own ship???s position *(latitude/longi- tude), Net sonde data *(net depth, distance to seabed, water temperature, sinking speed of net)

(6) Features

Custom mode, interference rejector, afterglow, noise lim- iter, delete color, memory card (save and recall of picture, echo inside estimate mark and net shooting data), auto- matic tilt, automatic target tracking, *(target lock), external KP sync, heading up, north up*, fish alarm, overvoltage warning, unretracted transducer warning, remote control

*: External sensor required.

3. HULL UNIT

SP-3

INDEX

IN-1