Furuno CSH-5 MARK-2 User Manual

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COLOR SCANNING SONAR

CSH-5 MARK-2

(

9-52, Ashihara-cho, Nishinomiya, Japan

Telephone: 0798-65-2111 Telefax: 0798-65-4200

Printed in Japan

Your Loc al Agent/Dealer

FIRST EDITION : NOV. 1995 E : DEC. 6, 2000

PUB. No. OME-12990

DAMI)

CSH-5 MARK2

SAFETY INSTRUCTIONS

WARNING

ELECTRICAL SHOCK HAZARD

Immediately turn off the power at the switchboard if water leaks into the equipment or something is dropped in the equipment.

Continued use of the equipment can cause fire or electrical shock. Contact a FURUNO agent for service.

Do not disassemble or modify the equipment.

Fire, electrical shock or serious injury can result.

Do not open the equipment.

Only qualified personnel should work inside the equipment.

WARNING

Keep heater away from equipment.

A heater can melt the equipment’s power cord, which can cause fire or electrical shock.

Use the proper fuse.

Fuse rating is shown on the equipment. Use of a wrong fuse can result in equipment damage.

Do not operate the equipment with wet hands.

Electrical shock can result.

Do not place liquid-filled containers on the top of the equipment.

Fire or electrical shock can result if a liquid spills into the equipment.

Immediately turn off the power at the switchboard if the equipment is emitting smoke or fire.

Continued use of the equipment can cause fire or electrical shock. Contact a FURUNO agent for service.

Make sure no rain or water splash leaks into the equipment.

Fire or electrical shock can result if water leaks in the equipment.

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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.

A warning label is attached to the equipment. Do not remove the label. If the label is missing or damaged, contact a FURUNO agent or dealer.

WARNING

To avoid electrical shock, do not remove cover. No user-serviceable parts inside.

Name: Warning Label (1) Type: 86-003-1011-0 Code No.: 100-236-230

1. FOREWORD _________________________________________ 1

2. SYSTEM CONFIGURATION_____________________________ 2

3. CONTROLS _________________________________________ 3

Operating Controls .......................................................................................................... 3

Main Panel .......................................................................................................................4

Control Box Panel ...........................................................................................................5

Menu Screen .................................................................................................................... 7

4. BASIC OPERATION __________________________________ 10

General .......................................................................................................................... 10

Turning the Power On/Off.............................................................................................10

Lowering the Transducer............................................................................................... 11

Selecting a Display Range .............................................................................................11

Setting the Tilt Angle ..................................................................................................... 11

Adjusting the Gain......................................................................................................... 15

5. FINE TUNING THE PICTURE___________________________ 16

General .......................................................................................................................... 16

Eliminating Unwanted Feeble Echoes...........................................................................16

Displaying Surface Fish Clearly.................................................................................... 17

Suppressing Seabed Tail ................................................................................................17

Suppressing Seabed and Sea Surface Reflections in Shallow Fishing Grounds ........... 18

Rejecting Sonar Interference and Noise ........................................................................ 18

Selecting Horizontal Beamwidth................................................................................... 19

Selecting Vertical Beamwidth........................................................................................ 19

6. ADVANCED OPERA TION______________________________ 20

General .......................................................................................................................... 20

Measuring Range and Bearing to a Target.....................................................................20

Detecting Fish Schools Aurally .....................................................................................20

Relocating Fish School for Easy Observation ...............................................................21

Finding Fish School Center ........................................................................................... 22

Registering F1/F2 (function) key and Recalling ........................................................... 22

7. MARK AND DATA____________________________________ 24

Marks .............................................................................................................................24

Data................................................................................................................................25

8. INTERPRETING THE DISPLAY _________________________ 26

General .......................................................................................................................... 26

Interpreting the Display .................................................................................................26

iii

9. WARNING __________________________________________ 30

Overvoltage W arning.....................................................................................................30

Unretracted Transducer Warning................................................................................... 30

10. MENU ____________________________________________ 32

General .......................................................................................................................... 32

Changing Menu Settings ............................................................................................... 32

11. INTERFACE MODULE CSH-5060 ______________________ 35

Specifications................................................................................................................. 35

Operation .......................................................................................................................36

Indications .....................................................................................................................47

Marks and Data.............................................................................................................. 51

Event Mark Position Output ..........................................................................................52

12. MAINTENANCE ____________________________________ 53

General .......................................................................................................................... 53

13. UNIT DIAGNOSTIC TESTS ___________________________ 54

Description of Unit-diagnostic Tests .............................................................................54

14. CHARACTERISTICS OF THE ULTRASONIC WAVE IN WATER___________________________________________ 58

Sound Velocity...............................................................................................................58

Absorption and Attenuation........................................................................................... 59

Refraction ......................................................................................................................60

Adverse Effect of Air Bubbles....................................................................................... 61

Reflection at Seabed and Fish School ........................................................................... 62

SPECIFICATIONS____________________________________ SP-1 INDEX

1. FOREWORD

The FURUNO CSH-5 MARK-2 Color Scanning Sonar is a fullcircle,multibeam electronic scanning sonar which detects and instantaneously displays fish schools and underwater conditions in 16 colors on a 14" non-glare, high resolution CRT screen. Its ease of operation, versatility and compact size make it the perfect match for any class of fishing vessel.

Some of the prominent features of the CSH-5 MARK-2 are as follows;

• Compact 8" tube retraction tank

• V ivid 16-color display greatly improves recognition of seabed, and concentration, distribution and volume of fish schools.

• Various on-screen indications keep operator abreast of fishing conditions.

• Change of control setting is indicated by displaying the new setting in larger characters for five seconds.

• High power MOS FET transmitter ensures reliable operation under any condition.

• Control box, for operation from a distance.

The CSH-5 MARK-2 is a highly sophisticated instrument which performs its intended functions only when operated properly . Please carefully read and follow the recommended procedures for operation and maintenance to take full advantage of the many features this unit has to offer.

2. SYSTEM CONFIGURATION

System Configuration

Operating Controls

The CSH-5 MARK-2 provides intuitive operation. If you change a control setting you will see the associated reaction on the screen almost immediately . All operations are carried out from the main panel and the control box. The front panel incorporates mainly controls which do not require frequent adjustment, such as brilliance, interference rejector, and audio volume. The control box, which is connected to the display unit via a 7 m-long connection cable, houses the mostoften used functions, including transducer operation controls, and range and gain controls.

3. CONTROLS

DISPLAY UNIT

CONTROL BOX

Main Panel

DEMAG Button demagnetizes the display for cleaning irregular picture color.

Control Panel

Main Panel

AGC suppresses the echo tail of strong targets, e.g., the seabed, for easy recognition of fish schools adjacent to the sea bottom. Position "1" or "2" is the normal setting.

NOISE LIM is used to reject noise which is displayed over the screen in light blue. Position "3" is the normal setting.

NOISE LIM

OFF

CONTRAST

AUDIO

OFF

AGC

BRILL

DIMMER

POWER

COLOR SCANNING SONAR

VP (Video Processor) adjusts the after-image of the echoes for

proper period; echoes are stretched in the radial direction. Set at "1" for ordinary use.

IR (Interference Rejector) rejects random noise and interference caused by other echo sounders or sonars.

BRILL adjusts brightness of the screen in eleven steps.

CONTRAST adjusts the range of brightness between

highlights and shadows on the produced image.

DIMMER adjusts panel (main panel and control box panel)

illumination.

AUDIO controls the volume of the built-in loudspeaker for monitoring a target echo appearing the bearing mark.

POWER switches on and off the entire system.

Note:

When the power is turned off before r etracting the transducer, the transducer is automatically retracted. However, for safety purposes, do not forget to retract the transducer before turning the power off.

Control Box Panel

TRANSDUCER retracts and lower the transducer. The lamp above the switch flickers while the transducer is moving and lights when stopped.

TX turns on the transmitter, freeze the display and turns off the transmitter. The light above the switch is on when the transmitter is turned on and flickers when off.

Note: The transmitter is turned off when the transducer is retracted even if

the light above the TX switch is on.

MENU turns the menu display on and off.

TRANSDUCER

RANGE

AUTO

MENUTX

TILT

SECTOR

SCAN

-+-+

GAIN

EVENT

DELETE

R/B

OFF-

CENTER

GAIN adjusts the receiver sensitivity.

Adjust it for clear presentation of fish school echoes. This control is also used to change settings on menu screens.

RANGE selects a picture display range. This control is also used to select items on menu screens. Note that this control endlessly turns in both directions.

TILT

TILT continuously varies the tilt

angle of the sounding beam between 0° and - 55°. The operating angle is always indicated on the screen.

TRACKBALL moves the trackball mark ( ) to a desired position. The trackball mark data, i.e., slant range, horizontal range, depth and bearing to the mark, are always indicated on the screen. Additionally, this control is used to position the own ship’s mark, enter event marks and set the alarm.

EVENT

EVENT displays the latest event mark “ + ” and its position data; i.e.,

horizontal range, depth and bearing measured from own ship’ s position. (optional interface board is required to use this function.)

EVENT

DELETE

R/B

OFF-

CENTER

To delete event mark, locate the cursor on a event mark you want to delete and press EVENT DELETE key.

R/B draws a straight line, called Bearing Mark, from own ship position mark “ draws a circle called Range Mark with a radius of

” toward the trackball mark “ ” and simultaneously

to . Range and bearing data of the intersection of the two marks are displayed on the lower center of the screen. T o turn off the range and bearing marks, move the trackball mark near the own ship position mark and press the R/B key.

OFF-CENTER moves the own ship’s mark to a desired location on the screen in steps of 1/6 of screen radius. To off center the screen, place trackball mark on location to offcenter and press the OFF-CEN-

TER key. To reset the off-centered own ship’ s mark, press the OFF- CENTER key again.

AUTO

TILT

SECTOR

SCAN

F1 F2

AUTO TIL T automatically tilts the sounding beam up and down within

the tilt angle set on the menu screen.

SECTOR SCAN scans the bearing mark in 2° steps within the area selected on the menu screen. The echoes along the marker can be monitored thru the built-in speaker. The lamp at the left of the switch lights during sector scanning.

These keys provide user-defined sonar setting by one key operation. These keys have factory settings. See page 22.

Menu Screen

The CSH-5 MARK-2 employs four menu screens; menu-l, menu-2 and system menu. Of the four menus, the menu-2 and system menu contain preset items which do not require setting alteration if they are once set at installation. See page 32 for further details. The menu-l contains items to be set by the operator while using the sonar, taking the fishing ground and fishing method into account. This menu can be recalled on the lower part of the screen as “scan menu” during normal operation. This let you adjust setting while observing the sonar picture.

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Recalling Scan Menu

Press the MENU key , and 5 lines of the menu items are displayed on the lower part of the screen. Note that the scan menu can be recalled only when the transmitter is on.

SCAN MENU

HUE : 1 234

TX OUTPUT :8

PULSELENGTH : 7 TX CYCLE : 10 TVG NEAR : 6

( RANGE SW : U/D GAIN SW : L/R )

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Changing Setting

T o change a setting, select item with the RANGE control and setting with the GAIN control. The selected item is highlighted in green and the selected setting is circumscribed in white. T o scroll the menu items, turn the RANGE control counterclockwise.

Note:

The gain and range of the sonar picture can not be changed while the scan menu is displayed.

Turning Off Scan Menu

To turn off the scan menu, press the MENU key.

Note:

Settings for the items shown in red are locked. To unlock the

settings, call up the system menu. See page 33.

List of Scan Menu Items

SCAN MENU

HUE : 1 234

TX OUTPUT :8

PLUSELENGTH : 7 TX CYCLE : 10 TVG NEAR : 6 TVG FAR : 7 AUTO SCN WDTH : ± 10° ± 20° ± 40°± 60° AUTO TLT WDTH : ± 2°~10°± 4°~14° ± 6°~20° ± 10°~26° HOR BEAM ANGL : WIDE NARROW VER BEAM ANGL : WIDE NARROW RES COL CURVE : LINER 1 2 3 COL EMPHASIS : 1 (LOW) 2 3 4 (HIGH) FUNC KEY PROG : FUNC1 FUNC2 FACTORY

( RANGE SW : U/D GAIN SW : L/R )

Contents of Scan Menu

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General

4. BASIC OPERATION

This section provides information necessary for basic operation of the CSH-5 MARK-2, from turning the power on and off to detecting and tracking fish schools. The basic operating procedure is shown below.

Basic Operating Procedure

CONTROL SETTINGS

OUTPUT 10 Location for magnetic function card

PL 10

TVG, (Far, Near) 5, 5

AGC 0

NOISE LIM 3

VP 1

IR OFF

2/7 Lower/raise transducer. 4 Turn transmitter on.

6 Adjust gain. 3 Select display range.

Turning the Power On/Off

1/8 Turn power ON (OFF).

5 Set tilt angle.

Power On

Press the POWER switch on the main panel. The lamp at the left of the switch lights.

Note:

The Display and the Transceiver are checked for proper operation each time the power is applied. The check is explained in greater detail in a later chapter.

Power Off

CAUTION

Press the TRANSDUCER “ ” switch on the control box. W ait until the lamp above the switch lights, and then press the POWER “OFF” switch. Note that the transducer automatically retracts into the tank even if the POWER “OFF” switch is pressed without raising the transducer (by pressing the TRANSDUCER “ ” switch). However, for safety purposes, it is recommended that you make a habit of pressing the TRANSDUCER “ ducer is retracted.

Lowering the Transducer

Press the TRANSDUCER “ ” switch. The lamp above the switch flickers, and then lights when the transducer is fully lowered.

” switch first to ensure that the trans-

CAUTION

Observe maximum allowable ship’s speed of 18 knots during operation and 16 knots while raising/lowering transducer.

Selecting a Display Range

The RANGE switch on the control box is used to select a display range. The range selected is displayed at the top center of the screen.

Setting the T ilt Angle

The tilt angle shows the direction to which the sound wave is emitted. When the sound wave is emitted horizontally , it is said to be zero (0) degrees and when emitted vertically , 90 degrees. T o set a tilt angle, operate the TILT lever for the desired angle while watching the tilt angle indication at the top right-hand side of the screen. The tilt angle can be set in one-degree steps within the range of 0 to 55 degrees.

Finding the proper tilt angle is of utmost importance when searching for fish. This unit, because of its compact size, is highly suited to coastal water fishing where the depth of the main fishing ground is from 50-l00 m. In this type of fishing ground it is imperative that the seabed echo be always displayed to properly distinguish between fish and the seabed. When selecting a tilt angle, keep the following points in mind.

Seabed Echo vs Tilt Angle

Case 1: Tilt Angle 30 to 40 degrees A wide 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 A narrow tilt angle will display only half the seabed since it is cap-

tured by only the lower half of the beam. Case 3: Tilt Angle 0 to 10 degrees An exceptionally narrow tilt angle may or may not capture the sea-

bed since the returning echo is weak.

Example of How to Discriminate Fish Echoes from the Seabed

The following figure illustrates how two fish schools a and b are displayed on 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.

Case 1 Case 2 Case 3

Fish School a

Seabed

Fish School a

Seabed

Case 1 Case 2 Case 3

Points to Consider

• As a general rule of thumb, a vertically distributed fish school is a better sonar target than the seabed, since it reflects the transmitted pulse back toward to the source.

• In case 3, both fish schools a and b are presented. Generally speaking, however, midwater fish schools tend to be larger than bottom fish schools and they are often displayed near the seabed on the sonar screen.

• Detection of bottom fish is difficult if they are not distributed ver tically.

Tilt Angle for Surface Fish

Sound emitted from the sonar transducer forms a circle-shaped beam with a width of approximately 13 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 a half of the emitted sound to be reflected back toward the transducer and displayed on the screen as sea surface reflections. 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 dominant and will interfere with observation of wanted echoes. To minimize these sea surface reflections and to search surface fish schools effectively, the tilt angle is usually set to 5-6 degrees so that the upper portion of the beam becomes almost parallel with the sea surface. When the sea is rough, it is often set to a little larger angle.

SEA SURFACE SEA SURFACE

TILT 0°

13°

TILT 7°

13°

Suitable Tilt Angle

The figure on the next page 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.

Range

0°

5°

10°

15°

68m

300m

Tilt angle vs. Beam Coverage

100 (200) 200 (400) 300 (600) 400 (800)

TIL T ANGLE

20 (40)

40 (80)

60 (120)

80 (160)

100 (200)

46m

200m

23m

100m

13°

Vertical Width of Sonar Beam

200 (400)

Depth

Adjusting the Gain

The gain should be adjusted to see fish echoes clearly with minimal noise on the screen. Too high a setting not only causes excessive noise on the screen and makes it difficult to discriminate wanted fish echoes but also causes seabed echoes to be painted in strong colors, resulting that the echoes from bottom fish are masked by seabed reflections. Normally, positions “3” thru “7” are used.

Gain Low Gain Proper Gain High

5. FINE TUNING THE PICTURE

General

In the previous chapter basic operation of the sonar was presented. This chapter describes the procedures for fine tuning the sonar picture.

Eliminating Unwanted Feeble Echoes

Echoes from targets such as seabed and fish return to the transducer 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 displayed on the screen. T o overcome this inconvenience, the TVG function is incorporated. It compensates for propagation loss of sound in water; amplification of echoes on short rang is suppressed and gradually increased as range increases so that similar targets are displayed in the similar intensities irrespective of the ranges to them.

The CSH-5 MARK-2 incorporates two TVG function, NEAR and FAR, and they mainly compensate for propagation loss on short and long ranges respectively , centered at the ranges shown below. Setting a TVG in the scan menu larger (smaller) increases (decreases) amplification of echoes.

NEAR

400m

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 obtain the proper TVG setting, follow the procedure below.

FAR

TVG Setting Procedure

1. Set the TVG menus NEAR to “5” and FAR to “5”. These are the

standard setting and you can maintain these settings in most cases.

2. When sea surface reflections or plankton layers disturb the pic-

ture, adjust the NEAR control to eliminate them. They will be eliminated by decreasing the control setting by “1” or “2”.

3. Locate a fish school on a long range setting which is approaching own ship. Note that the tilt should be kept adjusted so that the fish school is always placed in the center of the sonar beam, i.e., so that the fish school is displayed in strongest colors possible. Check that the fish echo is displayed in the same color while it approaches. If the color changes suddenly to weaker colors as the fish echo enters FAR and NEAR areas, the TVG is improperly set. Adjust the TVG in the scan menu to correct it. If this again produces sea surface reflections and noise, try to remove them with the AGC and NL controls as described later on.

Displaying Surface Fish Clearly

When you are searching for surface fish with the tilt set to a narrow angle, sea surface reflections may disturb or mask wanted fish echoes. In this case, in addition to the TVG adjustment described earlier adjust the AGC control between positions “0” thru “3”.

Suppressing Seabed Tail

As noted earlier, fish schools (echoes) located near the seabed are sometimes difficult to detect because you have to discriminate them in the seabed reflections. The AGC control and PULSELENGTH in the scan menu, if used properly, decrease the tail of seabed reflections, making it easier to discriminate bottom fish.

AGC Control

The AGC control 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 re- flections. Do not turn it too far clockwise.

PL (Pulselength)

The pulselength control determines the length of the transmission pulse emitted into the water. While a longer pulse is advantageous for long range sounding, it has the disadvantage of being poor in discrimination of targets, i.e., ability to separate several closely located targets. When searching bottom fish, therefore, it is useful to shorten the pulselength in order to separate fish echoes from seabed reflections. Decrease the PL setting to shorten the pulselength in the scan menu. For search of surface and midwater fish in which seabed reflections are not so strong, the longest pulselength “ 10” should be used.

Suppressing Seabed and Sea Surface Reflections in Shallow Fishing Grounds

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 setting the OUTPUT in the scan menu without turning down the gain. The picture becomes clearer when output power is reduced rather than when the gain is decreased as illustrated below.

Fish echo

No Good

Good

TVG & AGC adjusted with OUTPUT maintained high

OUTPUT decreased with gain maintained constant.

Rejecting Sonar Interference and Noise

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

Fish echo weakened

Fish echo

Identifying Noise Source

To eliminate noise effectively, you should first identify the noise source.

* T urn off the TX switch on the control box and operate all on board

equipment one by one while observing the picture.

* Run the boat at various speeds to check if the noise is speed de-

pendent.

If neither of the above two steps has effect on the picture, adjust the IR (Interference Rejector) and NOISE LIM (noise limiter) controls as follows.

Rejecting Noise with IR Control

This control is similar to the interference rejector on echo sounders and radars. It is effective for rejecting random noise and sea surface reflections in rough sea conditions. Set the IR control to positions “1” thru “3” so that noise is just eliminated. Do not use an unnecessarily high setting since it may also reject small wanted echoes.

Rejecting Noise with NOISE LIM Control

W eak, unwanted reflections, colored light blue or green, are displayed when water is contaminated or plankton layers exist or due to ship’s noise. These echoes gradually become bluish as the NOISE LIM control is turned clockwise. Usually position “3” to “4” is used.

Rejecting Interference with TX Cycle

When other sonars operate nearby at the same transmission interval as that of own ship’s sonar, interference ring caused by other sonars are displayed. To erase the interference ring from the screen, reduce the TX cycle setting on the scan menu screen. See page 8.

Note:

When the sonar is used in a shallow water with the range set between 100 m and 200 m and the TX cycle at “10”, seabed reflections caused by the transmission which is the last but one on near range on screen. Reduce the figur e of TX cycle to “7” or “8” to reject them.

Selecting Horizontal Beamwidth

If you wish to have better bearing discrimination* for fish schools and also wish to examine the contour of seabed, call up scan menu and select “narrow horizontal beam width”.

Interference

* Ability to distinguish two closely located targets at the same range

and different bearings.

Selecting Vertical Beamwidth

When better detection range is required, call up scan menu and select “narrow vertical beamwidth”.

6. ADV ANCED OPERA TION

General

It this section, how to use the CSH-5 MARK-2 effectively in actual fishing operations is presented.

Measuring Range and Bearing to a Target

To measure the range and bearing to a target, use the trackball.

Procedure

1. Operate the trackball to place the trackball mark “ ” on the target you want to measure the range and bearing. The range and bearing are displayed at the left top on the screen.

Slant Range

Horizontal Range

Depth

bearing

Note:

The 360° or 180° indication system can be selected on the menu-2. See page 33.

The bearing is shown in either 360° or 180° indication system relative to the ship's heading. In the latter case, “B” is indicated as follows.

B P ------- on the port side B S ------- on the starboard side

Detecting Fish Schools Aurally

Trackball Mark

Occasionally you will 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 become accustomed to utilizing the audio function, you should be able to detect a fish school from a range longer than you can detect it on the screen.

Procedure

1. Move the trackball mark “ ” to the direction you want to moni-

tor through the speaker, by operating the trackball.

2. Press the R/B key . The bearing marker will appear in the direction

of the trackball mark and echoes in that direction are monitored through the speaker. Adjust the volume with the AUDIO control on the front panel.

To cover a certain area, press the SECTOR SCAN key. The bear- ing marker automatically scans in 2° steps starting from the bearing set at step 2 to cover the selected sector, giving you audio in the directions of 2° steps.

T o change the coverage area call up scan menu, and then select an auto scan width with the GAIN control; ±10°, ±20°, ±40°, ±60°.

To turn off the audio function, erase the bearing marker by placing the trackball mark on own ship mark and then pressing the R/B key.

Trackball Mark

Bearing Marker

Auto Scan Width

Own Ship Mark

Relocating Fish School for Easy Observation

When a fish school is located near the edge of the screen and inconvenient for observation, use the off-center function to relocate the fish school to the desired place on the screen.

Fish School

Off-center "ON"

Fish School

Own ship Mark

Trackball Mark

Procedure

1. Move the trackball mark “ ” to the position where the own ship

mark is to be moved.

2. Press the OFF-CENTER key on the front panel.

3. T o move the own ship mark back to the center of the screen, press the OFF-CENTER key again.

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.

Procedure

1. Call up the scan menu, select the menu item “AUTO TL T WDTH” and then choose a tilting width. The center tilt angle of the scanning is set by the TILT lever.

Both center and current tilt angles are displayed along with the range data at the upper right corner on the screen.

R 800 T 8°

(10° )

Range

Angle set by TILT lever

Present tilt angle

Registering F1/F2 (function) key and Recalling

Function keys provide user defined sonar settings by one key operation.

Default setting

These keys are preset at factory for one key operation as follows;

F1 : For detection of near range

TX OUTPUT PULSELENGTH TX CYCLE TVG NEAR TVG FAR HOR BEAM ANGLE VER BEAM ANGLE RES COL CURVE COL EMPHASIS

(Factory setting)

8 7

6 6

NARROW

WIDE

3 2

F2 : For detection of far range

TX OUTPUT PULSELENGTH TX CYCLE TVG NEAR TVG FAR HOR BEAM ANGLE VER BEAM ANGLE RES COL CURVE COL EMPHASIS

Angle set by TIL T lever

10 10 10

8 NARROW NARROW

LINEAR

Three magnetic function cards are supplied for indication of function settings. Two of these cards are inscribed with the factory setting of F1 and F2. The other card is blank for recording user settings. You can attach the card on the main panel for reference. See page 10.

Registering Procedure

1. Press the MENU key.

2. Rotate the RANGE control to select FUNC KEY PROG.

3. Rotate the GAIN control to select FUNC1 or FUNC2.

4. Press the TX key. Each time the TX key is pressed, the current

settings in the scan menu and E/S menu are recorded.

When FACTORY is selected, the default value is displayed.

Recalling Procedure

1. Press F1 or F2. Presetting function is recalled and function indi-

cation (LED lamp) lights.

Canceling the recalling

1. Press F1 or F2 again. The LED lamp goes off.

Recommended Settings

We recommend the function key be set as follows,

For detection of surface fish school

TX OUTPUT PULSELENGTH TX CYCLE TVG NEAR TVG FAR HOR BEAM ANGLE VER BEAM ANGLE RES COL CURVE COL EMPHASIS

8 7

5 NARROW NARROW

LINEAR

For detection of midwater fish

TX OUTPUT PULSELENGTH TX CYCLE TVG NEAR TVG FAR HOR BEAM ANGLE VER BEAM ANGLE RES COL CURVE COL EMPHASIS

7 NARROW

WIDE

For detection of bottom fish

TX OUTPUT PULSELENGTH TX CYCLE TVG NEAR TVG FAR HOR BEAM ANGLE VER BEAM ANGLE RES COL CURVE COL EMPHASIS

7 5

5 6

NARROW

WIDE

3 1

TRACKBALL MARK DATA

Slant Range

Horizontal Range

Depth

True Bearing

TRACKBALL MARK

HEADING MARK

7. MARK AND DATA

This chapter describes the marks and data which appear on the display screen.

RANGE TILT

AUTO TILT GAIN

BEARING MARK RANGE MARK

OWN SHIP MARK

Marks

RANGE RING

BEARING OF BEARING MARK

RANGE TO RANGE MARK

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The bearing is shown in either 360° or ± 180° indication system relative to ship’s heading. In the latter case, "B" is indicated as follows.

B B

Shows the range scale set with the RANGE switch.

P ------- on the port side S ------- on the starboard side

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Tilt Data

Gain Data The gain set with the GAIN control is displayed in 0.5 steps between 0 G

Range/Bearing Mark Data

B R

Setting Change Data When the setting of the following switches is changed, the new setting is

(

)

The tilt angle set with the TILT level is displayed in 1° steps between 0° and 55°. When the auto tilt function is in operation, instantaneously changing present tilt angle is indicated below it; ( ).

and 10. The slant range to the range marker and the bearing of the bearing mark

is displayed.

noted in larger characters for about five seconds at the top of the screen. The current tilt angle and sector range are also displayed upon switching on the AUTO TILT switch.

Switches TILT GAIN RANGE

Display

Switches

AUTO TILT SPD AUTO SCAN WDTH

Display

± ±

° °

8. INTERPRETING THE DISPLAY

General

This section provides information necessary for interpreting the display .

Interpreting the Display

Seabed

When the tilt angle is changed, the seabed echo illustrated below will appear on the screen. When the tilt angle is decreased, the seabed trace becomes wider and weaker . By observing the seabed condition on the screen, the skipper can prevent the net from being damaged by a reef or a shipwreck.

(a) Flat Seabed

Tilt Angle: 10° - 15°

(b) Flat Seabed

Tilt Angle: 20° or more

Seabed Echo

Narrow tilt angle; only half of vertical beam width captures the seabed.

Seabed Echo

Seabed is displayed narrower and in a stronger echo colors compared to (a).

A shallow bottom is displayed in a strong echo color and with a short tail.

The deeper seabed echo in a displayed in a weak color and with a long tail.

Seabed

Fish School

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 know the distribution and center point of a fish school, the tilt should be changed to several different angles.

(a) Sea Surface Fish

Tilt Angle: +5° - 10°

(b) Midwater, Bottom Fish

Fish echo appears before seabed echo Tilt Angle: 30° or more

Fish school

Sea Surface Reflections

Seabed

Because of the narrow tilt angle, seabed echo is not displayed. Sea surface reflections are present.

Fish echo appears together with or after seabed echo Tilt Angle: 0° - 20°

Fish school

Large midwater fish school is present.

Fish School

Seabed

Since the seabed is displayed in weak echo colors, longer range detection and detection of close to bottom fish school become possible.

Sea Surface Reflections

To reduce the sea surface reflections, set the tilt angle to 5° or more so that the upper edge of the sonar beam may not hit sea surface, or adjust TVG functions. When the sonar is used with a narrow tilt angle, the sea surface reflections cover large area (up to 300 m to 400 m) as illustrated below.

Tilt angle 0°

Tilt Angle 5° - 6°

Other Ship

SEA SURFACE

13°

SEA SURFACE

13°

Tilt Angle Indication

Sea Surface Reflection

Wake

Awake produced by own ship or another ship can be a strong reflecting object when the sonar is used with a narrow tilt angle. As the wake appears on the screen as a thick continuous line, it can be easily distinguished from a fish school. On the other hand, the wake contains a lot of air bubbles which attenuate ultrasonic energy , making it often difficult to sound beyond the wake.

Own Ship

Tilt Angle : 0 - 10°

Own Ship’s Screw Noise

Wake produced by other ship

Own Ship’s Screw Noise

Own Ship’s Wake

Wake produced by own ship when ship is turned

False Echo by Sidelobe

In the preceding chapters, it was explained that an ultrasonic wave is emitted only in the direction set by the TILT lever, but, in practice, there are some emissions outside the main beam that are called “sidelobes”. Energy of the sidelobe is fairly weak but when the sonar is used in comparatively shallow water with a hard and rocky bottom, strong target signals are detected by the sidelobe. These are represented on the screen as a false echo as shown below . T o weaken the sidelobe echoes, set the VER BEAM ANGLE to WIDE on the SCAN MENU.

Mainlobe echo

Sidelobe echo

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

Noise and Interference

In case the fishing ground is crowded with many fishing boats, the sonar is subject to interference from ultrasonic equipment such as an echo sounder, sonar, etc. on board other boats as well as those on board own ship.

For instance, interference from the sonar operated on board other boats will appear as a ring as shown in (A). This interference can be suppressed by properly changing TX cycle. Electrical equipment on own ship can also cause interference to the sonar as shown in (B). The noise from some marine life appears on the screen as in (C). This noise can be suppressed by the IR control.

(A) (B) (C)

Noise and Interference

Overvoltage W arning

If the supply voltage rises about 20% to over the rated value, the overvoltage detection circuit is actuated. The following warning flickers at the center of the screen and an alarm sounds.

OVERVOLTAGE!

If this occurs, retract the transducer, turn the POWER off and check the ship’s mains (and the stepdown transformer if provided).

Unretracted Transducer Warning

When the transducer can not be completely retracted within 35 seconds after pressing the TRANSDUCER “ ” switch, the following warning flickers at the center of the screen and an alarm is released.

9. WARNING

XDCR NOT RETRACTED!

If this occurs, do the following.

1. The POWER switch can not be turned of f because the transducer

can not be retracted. Turn off the main breaker for the transceiver unit to stop operation.

2. Confirm that the net is not entwined around the transducer.

3. Confirm that the breaker inside the raise/lower control box mounted on the hull unit is “ON”.

4. Check the mains fuse in the transceiver unit.

5. Apply the power again and confirm that the transducer is retracted into the tank. If not, the main shaft of the hull unit may be bent. Cut off the power again and manually raise the transducer up to the highest position by using the hand crank attached to the hull unit.

Hand Crank

Down Command LED (Red)

Power LED (Green)

Bottom

Power SW

Breaker

Power switch (Normally " " position)

hull unit

OFF

Main Fuse

Fuse for Transceiver

Transceiver Unit

General

The CSH-5 MARK-2 employs three menu screens, menu-1 menu-2, and system menu, to preset infrequently used functions.

Changing Menu Settings

Procedure to Change Menu Settings

1. Turn off the transmitter with the TX key; LED flickers.

2. Press the MENU key. The menu-1 appears.

3. To select another menu, operate the GAIN control.

4. Select a menu item with the RANGE switch and change the setting with the GAIN control.

10. MENU

Note:

Setting for the items shown in red are locked. To unlock the settings, change the “menu select” setting on the system menu.

Menu-1

The figure below shows menu-1. The contents of the menu-1 are same as the scan menu described on

page 8.

** SCAN MENU ** ( RANGE SW : U/D GAIN SW : L/R)

[MENU MODE] : MENU-1 MENU-2 SYSTEM HUE : 1 23 4

TX OUTPUT :8

Menu-2

The figure below shows menu-2.

** MENU 2 **

MENU MODE : MENU-1 MENU-2 SYSTEM

EXT KP OFF ON RANGE MARKER 1/4R 1/2R OFF MARK INDI ±180° 360°

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System Menu

The figure below shows the system menu.

** SYSTEM MENU ** ( RANGE SW : U/D GAIN SW : L/R) [MENU MODE] : MENU-1 MENU-2 SYSTEM

HEADING ADJ : 0°

AUTO SCN SPD : LOW HIGH

AUTO TLT SPD : LOW HIGH UNIT : METERS FEET FATHOMS PA/BRA MENU SELECT : LOCK UNLOCK SUB TEXT INDI : OFF ON LANGUAGE : ENGLISH (JAPANESE) ESPANOL DANSK SELF TEST : SINGLE PANEL COLOR GRAY

CONTI SIO ECHO-1 ECHO-2

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11. INTERFACE MODULE CSH-5060

Specifications

The CSH-5060 Interface Module permits connection of external equipment (navigational equipment, current indicator, echo sounder, net sonde, gyrocompass, log, etc.) to display various data on the CSH-5 MARK-2.

1. Display Mode

(a) Normal (b) Normal + Text (c) Echo Sounder Combination (Normal + Echo Sounder) (d) Sonar Combination (Normal + Signal on R/B Mark)

(a) (b)

9/10

1/10

(c)

3/5

2/5

3/5

2/5

(d)

2. Display Mark

Course line mark, Current mark, Event mark, Electronic bearing scale, Heading mark, and Net sonde data are graphically displayed on the Echo Sounder Combination mode.

3. Numeric Information

Event Mark Data (Horizontal range, Depth, Latest event marked

depth and Bearing)

Navigational Data (Ship’s speed, Heading, Water depth, Tempera-

ture) Position Data (Latitude, Longitude) Tidal Current Data (Speed, Direction)

Operation

AUTO

EVENT

TILT

SECTOR

EVENT

SCAN

GAIN

DELETE

R/B

OFF-

CENTER

TRACKBALL

The functions of the Interface Module are accessed from the MENU screen except the Event mark and North mark*.

* —Gyrocompass required.

1. Event Mark and Own Ship Mark

Plotting

(1) Move the cursor to the location where you want to plot the

event mark.

(2) Press the EVENT key. The cursor is replaced with the latest

event mark [ ] and the event mark data (horizontal distance, depth and bearing) appears on the lower left side of the screen.

Note:

1. You can plot 10 event marks. (latest mark - , other 9 marks --- +)

2. You cannot plot the event mark at the own ship mark. In this case, the own ship mark is plotted (max.10).

TILT

Erasing

Locate the cursor on the event mark and press the EVENT DELETE key.

AUTO

TILT

SECTOR

SCAN

EVENT

DELETE

R/B

OFF-

CENTER

Target Lock Mark

2. Target Lock Mark

Use this mark when you want to track fish echoes automatically.

Plotting

(1) Select "TARGET" on the range/bearing item on the SCAN

Menu to activate the mark.

(2) Move the cursor onto the fish echo you want to track. (3) Press the R/B key. The bearing mark and the target lock mark

appear and start to track the fish echo.

Erasing

To exit from the tracking mode, press the R/B key again.

NOTE:

scan controls do not function.

When using the target (lock) mode the auto tilt and sector

LED lamp

TARGET LOCK FUNCTION

θ1

θ2

The target lock function allows continuous tracking at a present

depth "D". That is, the tilt angle changes automatically from "θ1" to "θ2" as the ship approaches the fish.

3. Erasing Weak Noise

Unknown weak noise appearing over the entire screen can be erased with DELETE COLOR, on the SCAN menu. Echoes are erased in order from weakest to strongest, so you may use this function to show only strong echoes.

1. Press the [MENU] key to turn on the menu.

2. Select DELETE COLOR with the RANGE control.

3. Use the GAIN switch to select desired setting. The setting range is 0-10. "0" turns off this function, 10 erases the strongest color echoes. Note that the echoes on the echo sounder and range and bearing mark display will also be erased.

4. Press the [MENU] key to close the menu.

4. Suppressing Effects of Pitching and Rolling

Tilting in bow direction

Bearing mark at 0° (bow direction); beam stabilized

Echo not captured by beam

Echo captured by beam

The Motion Sensor MS-100 (option) compensates for the effects of pitching and rolling to provide stable sonar pictures. You may enable it as follows:

1. Press the [MENU] key to display the SCAN menu.

2. Use the RANGE control to select RANGE/BEARING.

3. Use the GAIN control to select STAB.

4. Press the [MENU] key to close the menu.

5. Operate the trackball to place the trackball mark on the bearing you want to compensate by the MS-100.

6. Press the [R/B] key. A dashed line appears at the bearing selected at step 5. The rolling and pitching of the ship in the direction of the bearing mark is compensated, by automatically adjusting the tilt angle.

Picture in direction

selected with bearing

mark is compesnated.

Note: The entire picture is not compensated in the full-circle scan-

ning; the tilt angle for each bearing cannot be changed. Only one bearing is compensated and bearing error will result for any bearing not stabilized.

Tilt can be controlled manually from 0° to 55°, however rolling and pitching are compensated from -5° to 55° with the tilt angle at ±20°.

5. Detecting Fish Echoes in Specific Area (Fish Alarm)

The fish alarm alerts you to fish echoes in an area you select. Any fish echoes entering the area will trigger the audio alarm. The fish echo level which triggers the alarm may be selected from the scan menu.

1. Press the [MENU] key to open the SCAN menu.

2. On the scan menu, use the RANGE control to select RANGE/ BEARING.

3. Use the GAIN control to select FISH/ALM.

4. Use the RANGE control to select FISH ALARM.

5. Use the GAIN control to select ON.

6. Press the [MENU] key to close the menu.

7. Use the trackball to place the trackball mark on the starting bearing and press the [R/B] key.

8. Use the trackball to place the trackball mark on the ending bearing and press the [R/B] key.

Alarm area

Starting point

Ending point

To disable the fish alarm, press the [R/B] key.

Note: The starting point may be selected at the outside or inside of

the alarm zone. You may also set a 360-degree alarm by setting the starting and ending points within three degr ees of each other as in (c) and (d) in the figure below.

More than 3°

Within 3°

(a) (b) (c) (d)

TRANSDUCER

6. Fish Alarm On/Off, Fish Alarm Sensitivity

The audio alarm for the fish alarm can be enabled/disabled and the fish alarm sensitivity can be selected from the scan menu.

1. Press the [MENU] key to open the SCAN menu.

2. Use the RANGE control to select FISH ALARM.

3. Use the GAIN control to select the echo strength which will trigger the fish alarm. The setting range is 0 to 14. Choose "0" for no audio alarm. For example, selecting "4" will trigger the audio alarm when an echo whose strength is between 0 and 4 comes into the fish alarm zone.

4. Press the [MENU] key to close the menu.

7. Menu Screen

Recalling

AUTO

TILT

MENUTX

Press the MENU key. The SCAN MENU or E/S

SECTOR

on the lower part of the screen. Note that the SCAN or E/S MENU

SCAN

can be recalled only when the transmitter is ON.

*--When the Echo sounder combination mode is selected.

MENU appears

RANGE

Changing Setting

-+-+

To change a setting, select item with the RANGE control and setting with the GAIN control. The selected item is highlighted in green and the selected setting is circumscribed in white. To scroll

GAIN

the menu, turn the RANGE control counterclockwise.

Note:

The gain and range of the sonar picture can not be changed

while the scan menu is displayed.

Exit from Menu Screen

To exit from the menu screen and return to the sonar screen, press the MENU key.

Note:

Items shown in RED indicate they ar e locked to prevent alteration. To unlock a setting, call up the SYSTEM MENU.

8. Menu Description

The CSH-5 MARK-2 employs three menu screens, MENU-1, MENU2 and SYSTEM Menu, to preset infrequently used functions. During normal operation (transducer lowered, transmitter ON), the SCAN Menu appears on the screen. This lets you adjust settings while observing the sonar picture.

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9. Menu Screen Indications

MENU-1

** MENU-1 **

[MENU MODE] : MENU-1 MENU-2 SYSTEM DISPLAY MODE : COMBI 1 NORM TEXT COMBI 2

HUE : 1 2 3 4

TX OUTPUT :8

PULSELENGTH : 7 TX CYCLE : 10 TVG NEAR : 6 TVG FAR : 7 AUTO SCN WDTH : ±10° ±20° ±40°±60° AUTO TLT WDTH : ±2~10°±4~14° ±6~20° ±10~26° HOR BEAM ANGL : WIDE NARROW VER BEAM ANGL : WIDE NARROW RES COL CURVE : LINEAR 1 2 3 COL EMPHASIS : 1 (LOW) 2 3 4 (HIGH) FUNC KEY PROG : FUNC1 FUNC2 FACTORY E/S RANGE : 240 E/S SHIFT : 0 E/S IR : ON OFF E/S GAIN : 3.0 E/S CLUTTER : 2.0 E/S ADV ANCE : 1/1 1/2 1/4 1/8 E/S COL CURVE : LINEAR 1 2 3 E/S DRAFT : 0.0 (m)

( RANGE SW : U/D GAIN SW : L/R )

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: indicates the items which may be locked. : indecates the menu items available with the addition of

the CSH-5060 and external equipment.

MENU-2

** MENU-2 ** ( RANGE SW : U/D GAIN SW : L/R ) [MENU MODE] : MENU-1 MENU-2 SYSTEM

EXT KP SYNC : OFF ON RANGE MARKER : 1/4R 1/2R OFF BEARING SCALE : ON OFF CURRENT MARK : ON OFF COURSE MARK : 10R 5R OFF

HEADING INDI : 32-AZI TRUE

CURRENT INDI : 32-AZI TRUE ±180° 360° EVENT INDI : 32-AZI TRUE ±180° 360° MARK INDI : ±180° 360° POSITION DATA : L/L TD

SYSTEM MENU

** SYSTEM MENU ** ( RANGE SW : U/D GAIN SW : L/R ) [MENU MODE] : MENU-1 MENU-2 SYSTEM

HEADING ADJ : 0°

AUTO SCN SPD : LOW HIGH

AUTO TLT SPD : LOW HIGH UNIT : METERS FEET FATHOMS PA/BRA SHIP’S SPD/BR : LOG/GY CI NAV LOG PULSE : 200 400 CI BAUD RATE : 4800 2400 1200 NAV FORMAT : CIF NMEA183 NMEA182 NAV BAUD RATE : 4800 2400 1200 NAV DATA : GPS LC DEC DR

LA ALL COMBI SCALE : RIGHT LEFT MENU SELECT : LOCK UNLOCK SUB TEXT INDI : OFF ON LANGUAGE : ENGLISH (JAPANESE) ESPANOL DANSK SELF TEST : SINGLE P ANEL COLOR GRAY

CONTI SIO ECHO-1 ECHO-2

SCAN MENU

** SCAN MENU ** ( RANGE SW : U/D GAIN SW : L/R )

** SCAN MENU ** ( RANGE SW : U/D GAIN SW : L/R ) MENU MODE : SCAN E/S

MENU MODE : SCAN E/S

DISPLAY MODE : COMBI-1 NORM TEXT COMBI-2 HUE : 1 2 3 4

TX OUTPUT :8

PULSELENGTH : 7 TX CYCLE : 10 TVG NEAR : 6 TVG FAR : 7 DELETE COLOR : 0 AUTO SCN WDTH : ±10° ±20° ±40°±60° AUTO TLT WDTH : ±2~10°±4~14° ±6~20° ±10~26° MARK ERASE : COURSE SHIP EVENT RANGE/BEARING : NORMAL TARGET STAB. FISH/ALM FISH ALARM : ON OFFF ALARM LEVEL : 9 HOR BEAM ANGL : WIDE NARROW VER BEAM ANGL : WIDE NARROW RES COL CURVE : LINEAR 1 23 COL EMPHASIS : 1 (LOW) 2 3 4 (HIGH) FUNC KEY PROG : FUNC1 FUNC2 FACTORY

E/S MENU

** E/S MENU ** ( RANGE SW : U/D GAIN SW : L/R )

MENU MODE : SCAN E/S HUE : 1 23 4

E/S RANGE : 320

E/S SHIFT : 0 E/S IR : ON OFF E/S GAIN : 3.0 E/S CLUTTER : 1.0 E/S ADV ANCE : 1/1 1/2 1/4 1/8 E/S COL CURVE : LINEAR 1 2 3 E/S DRAFT : 0.0(m)

10. Contents of Menu Items

This section describes the menu items available with the addition of the CSH-5060 and external equipment.

MENU-1 (SCAN, E/S Menu)

Scan menu

Item

MENU MODE DISPLAY

MODE

DELETE COLOR

Contents

Selects a menu; MENU-1, MENU-2 or SYSTEM Menu. Selects a picture display mode among the four below.

9/10

1/10

NORM TEXT COMBI 1 COMBI 2

3/5 2/5

3/5

2/5

NORM: Normal Mode; displays a sonar picture on entire screen. TEXT: Normal + Text; The text area appears on the lower area. This area

is for displaying own ship’s position, ship’s speed, course, depth and tidal current.

COMBI 1: Sonar Combination (Normal + Signal on Bearing Mark); The

echoes on the bearing mark direction appears on the lower 2/5ths of the screen.

COMBI 2: Echo Sounder Combination (Normal + Echo Sounder); When an

external echo sounder is connected, the picture from the echo sounder appears on the lower 2/5ths of the screen.

Deletes echo colors whose strength is lower than the strength selected here. Useful for eliminating noise.

MARK ERASE (for scan menu only)

RANGE/ BEARING (for scan menu only)

Selects the item to erase with the [TX] key; COURSE (track), SHIP (own ship mark), EVENT (event mark). Each pressing of the key deletes eldest track, ship or event mark.

This menu chooses the function of the [R/B] key. NORM - The echoes in the direction designated by the bearing

mark are stabilized against the ship’s pitching and rolling. TARGET - Echo designated by the target lock mark is automatically tracked. STAB, - Compensates for the effects of pitching and rolling. Requires

Motion Sensor MS-100 FISH/ALM Enables the user to set the fish alarm zone.

FISH ALARM Disables/enables the audio alarm for the fish alarm.

ALARM LEVEL Chooses echo level which will trigger the fish alarm.

E/S Menu

Item

E/S SHIFT

E/S IR E/S GAIN E/S CLUTTER E/S ADVANCE

E/S COL CURVE

(Response Color Curve)

Contents

Shifts the start depth of the display range and the maximum value is about 1000 m irrespective of the depth unit. The unit shift value is determined by the range in use. See table below.

M FT FA P/B

1 220501010 3 40 100 20 20 4 50 100 25 25 5 50 200 40 40 6 100 200 50 50 7 100 300 50 50

Turns the Interference Rejector on and off. Controls the gain of the Echo Sounder picture. Eliminates the noise appearing on the screen. Adjusts the picture advancement speed. 1/1 is fastest, 1/8 is slowest. This menu sets the balance between weak and strong echoes. In the LINEAR

position, output (echo strength displayed) varies proportionally with input (actual echo strength). Select a higher setting to emphasize weak echoes. Weak echoes are displayed in stronger echo colors as the number goes higher. The standard setting is the LINEAR position.

25 5

E/S DRAFT

Adjusts the draft of the own ship according to loading conditions. Irrespective of the depth unit selection, the draft adjustment is available from 0 to 10 m in 0.5 m steps.

Selects the display range of the Echo Sounder from the table below.E/S RANGE

M FT FA P/B

110 2 3 4 5 6 7

Depth unit may be selected on the SYSTEM Menu.

20 40 120 20

80 240 40 120 360 60 160 480 80 240 720 120 320 960 160

60 10

20 40 60

80 120 160

MENU-2 (Refer to pages 47 to 51 for location on the screen.)

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Indications

1. Normal Mode (NORM)

Electronic Bearing Scale

Mark Indication (Bearing)

Heading Indication

Current Mark

Course Mark

Own Ship’s Mark

2. Normal + Text Mode

Current Indication

Position Data

Latest Event Mark Data

Past Event Mark

Navigational Data

3. Echo Sounder Combination Mode (COMBI 1)

Normal + Echo Sounder

Sonar Picture

16 Color Bar

Echo Sounder Picture

4. Sonar Combination (COMBI 2)

Normal + Signal on R/B Mark

Sonar Picture

16 Color Bar

Signal on R/B Mark

Marks and Data

This section explains the Marks and Data available from the equipment interfaced. Pages 24 to 25 show the location of these Marks and Data.

New Marks and Data

Latest Event Mark Data

)(

Own Ship’s Mark

Elecrtonic Bearing Scale

Course Line Mark

Current Mark

Description

The position data of the latest event mark, i.e., horizontal range (→), present depth (↓) and bearing. ( ) shows the latest event mark original depth which remains unchanged even if ship moves or tilt angle is changed. When the event mark is erased on the MENU screen, the above data disappear from the screen.

You can plot up to 10 own ship’s marks on the course line. The mark can be erased on the MENU screen.

The electronic bearing scale is available with gyrocompass connection. It rotates with own ship’s movement.

The own ship’s course line is plotted by a solid line when gyrocompass / speed log or a navigation device (GPS or Loran C) is connected. The course line length is selectable from 5 or 10 times the range in use. You can erase the line by the MENU screen.

When a current indicator is connected, the current mark shows the speed and direction of three current layers, numbered 1 through 3. The current speed is indicated by the length of the vector. However, no vectors are developed if the current speed is 0.1 knots or less. The vector shows current direction. The current mark can be erased on the MENU screen.

Tridal Current Data

C1: . C2: . C3: .

Navigational Data

S: . C: D: T: .

Own Ship’s Position Data

° .N ° .E

North Mark

Target Lock Mark

In the Normal Mode (with Text), current speed and direction for three current layers appear in the text area. The display method for the current direction can be selected on the MENU screen.

Own ship’s speed(S), heading(C), water depth(D) and water temperature(T) can be displayed on the text area when appropriate equipment are interfaced.

Own ship’s position is shown in the Normal (with Text) mode (Position fixing equipment is required.)

The north mark is available with gyrocompass connection.

In the target lock mode (automatic echo tracking), the target lock mark appears when the [R/B] key is depressed. To erase the mark, press the [R/B] key again.

Event Mark Position Output

Connected to a navigator, the CSH-5 MARK-2 can output event mark position data to external equipment when the [EVENT] key is operated. The data sentence output is "SSTLL" (NMEA, IEC-1162 format).

General

WARNING

CAUTION

WARNING

12. MAINTENANCE

The CSH-5 MARK-2 is designed and constructed to provide many years of trouble-free performance when properly maintained. Userperformable maintenance and important points to be observed are outlined in the figure below.

Do not open the cover of the equipment.

This equipment uses high voltage electricity which can shock, burn, or cause death. Only qualified personnel should work inside the equipment.

Keep screen and filter clean! Put on cover after operation.

Do not use thinner or benzine for cleaning. Use a water-moistened soft cloth.

Keep magnets and cassette tapes away!

Handle with care!

Corrosion may occur!

Keep heater away! Allow room for ventilation.

Display Unit

Apply MOLYTONE grease #2 every six months.

Color may become distorted!

CAUTION

The zinc block attached near the transducer must be replaced at periodic maintenance.

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

Raise transducer and apply DAPHAECOROAEX #2 over the main shaft every six months.

Reapply one coat of antifaulant "MARINE STAR 20 Mod (Red-N)" (no other paints are allowed) on the washed polyuretane transducer face upon dry-docking at least once a year, to prevent seashells and seaweeds from growing

Hull Unit

13. UNIT DIAGNOSTIC TESTS

This unit has eight built-in diagnostic tests which check it for proper performance. Although the tests are designed primarily for use by the service technician, they can also be executed by the user to identify defective components. However, never attempt to check inside the unit; there are no user-serviceable parts inside. Any repair work is best left to a qualified technician.

Turning-on/off Diagnostic Test

1. Press the MENU key, and then select the system menu by operating the GAIN control.

2. Select the “SELF-TEST’ function by operating the RANGE switch. Select an appropriate self-test by operating the GAIN control.

SUB LANGUAGE ENGLISH JAPANESE ESPANOL DAN SK SELF TEST SINGLE PANEL COLOR GRAY

CONTI SIO ECHO-1 ECHO-2

3. Press the TX switch to execute the self-test.

4. To exit from the self-test screen, press the MENU key for a few seconds. When the “SINGLE” is selected, the unit automatically restores the system menu after the test is completed.

Description of Unit-diagnostic Tests

Single Test

This test checks the Main Board and T ransceiver Unit for proper operation one time, after which normal operation is restored. After the test is completed, the results are indicated as OK (normal operation) or NG (malfunction), to the right of the device checked.

SINGLE TEST

∗∗∗∗: 0635 e 107kHz

0644 e 85kHz

MAIN 105-0541-XXX 105-0542-XXX

ROM = OK RAM = OK P.W = OK

TRX 105-∗∗∗∗-XXX 105-∗∗∗∗-XXX

ROM = OK RAM = OK

I/F 105-0267-XXX

ROM = OK RAM = OK

XXX : Version number

Display Unit Program No. is displayed and ROM, RAM and P.W (Password) are checked for proper operation.

TRX (Transceiver) Unit Program No. is displayed, and ROM and RAM are checked for proper operation.

ROM and RAM of the interface module CSH-5060 (option) are checked for proper operation. If the interface module is not provided, program number and check result are not displayed.

Conti Test

This is a continuous test of the Display and Transceiver Units. Additionally checked devices are DROM and DRAM.

CONTI TEST

MAIN 105-0541-XXX 105-0542-XXX

ROM = OK RAM = OK P.W = OK DROM = OK DRAM = OK DPRAM = OK

TRX 105-∗∗∗∗-XXX 105-∗∗∗∗-XXX

ROM = OK RAM = OK DROM = OK

I/F 105-0267-XXX

ROM = OK RAM = OK DPRAM = OK GYRO = OK LOG = OK

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

∗∗∗∗: 0635 e 107kHz

0644 e 85kHz

Not displayed if interface module CSH-5060 is not provided.

Panel Test

This test checks the controls on the front panel and the control box for proper operation.

PANEL TEST

00 00

••

000000

00 X=00

7 300 Y=0

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

Main Panel Press each control one by one.

The figure should change if the control is functioning properly.

Control Box Repeat the above procedure.

SIO Test

This test checks the input/output parts of the Transceiver Unit. The results of the test are indicated as OK or NG.

SIO TEST

MAIN SIO1 = OK

SIO2 = OK

I/F SIO-NAV= NG

SIO-CI = NG

SIO1: Checks communication line

between display and transceiver unit.

SIO2, SIO-NAV and SIO-CI check communication line between interface module (option) and display unit. Short-plug is required to conduct this test.

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

Color T est

The color test checks for proper display of all colors.

COLOR TEST

16 Color display

WHT RED GRN

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

Echo-1 Test

The echo-1 test checks echo processing circuits in the display unit for proper operation.

DISPLAY ECHO TEST

→

240

→

236

↓

281°

R29 B358°

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

R400 T10°

G3.0

Gray Test

The gray test checks for proper display of monochrome characters and markers. Concentric rings and a monochrome test bar are displayed.

GRAY TEST

............

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

Echo-2 Test

The echo-2 test checks echo processing circuits in the transceiver and display units.

PRESS [MENU] 2 or 3 SECONDS TO STOP SELFCHECK

Set the VP control on the main panel to "OFF" position. Radial pattern as above is displayed.

14. CHARACTERISTICS OF THE ULTRASONIC WAVE IN W ATER

The purpose of this chapter is to provide an overview of the characteristics of the ultrasonic wave in water.

Sound Velocity

It is generally known that an ultrasonic wave travels 1500 meters per second in sea water, but in practice, some amount of variation arises depending on the season and area from differences in the following three factors:

Water temperature .............................. θ [ C]

Salinity density ...................................S [%]

Water pressure (water depth)..............h [m]

°C

0 1 2 3 4 5 6 7 8 9

11 12 13 14 15 16 17 18 19 20

Therefore, for propagation in surface water the velocity changes not only by area but also by direction of the wave propagation. The equation obtained thru numerous measurements is;

C= 1410 + 4.21θ - 0.037θ

Velocity (m/sec)

1445.4

1450.0

1454.4

1458.8

1463.1

1467.2

1471.3

1475.3

1479.2

1483.0

1486.7

1490.3

1493.8

1497.3

1500.6

1503.8

1507.0

1510.0

1513.0

1515.9

1518.7

+ 1.145S + 0.0168h [m/s]

Correction value with respect to Depth and Temperature (m/s.)

Depth

(m)

°C

100 200 300 400 500 600 700

1.8 3.6 5.4 7.3 9.1 10.9 14.5

1.8 3.6 5.4 7.2 9.0 10.8 14.5

1.8 3.6 5.4 7.2 9.0 10.8 14.4

1.8 3.6 5.4 7.3 9.1 10.9 14.5

Fig.1 Sound Velocity

Research in the waters throughout the world has revealed that there is a difference of approximately 100 m/s between the areas where the velocity is maximum and minimum

Generally, the velocity increases as follows, provided that salinity density is constant:

• 3 m/s for every 1 degree rise of water temperature

• 1.7 m/s for every 100 m increase of water depth

Absorption and Attenuation

An ultrasonic wave emitted into water becomes weaker in intensity as it goes away from the emitting source. Principle causes of attenuation are:

1. Acoustic energy of the ultrasonic wave decreases gradually through reflection, refraction and diffusion in water.

2. Acoustic energy is absorbed by the viscosity of the medium (water) and converted into other forms of energy.

10000

1000

100

0.1

0.01

Absorption (db/km)

0.001

0.0001 10210310410510610

Frequency (Hz)

5°c

The higher the frequency, the greater the absorption and attenuation of the ultrasonic wave as shown below. In other words, the absorption coefficient is a function of the frequency . Generally , total ener gy loss encountered on the way to and from a target is expressed

TL [dB] = 40 logR + 2αR where R ----- Range to a target

α ----- Absorption coefficient

160 150

140 130

f=200kHz

120

α=64.5db/km

110 100

TL (db)

90 80

70 60

50 100 1000 10000

570m 2400m

f=200kHz α=33db/km

Range (m)

Refraction

An ultrasonic wave transmitted in water does not travel straight but is more or less refracted. This refraction is caused by the variation of propagation velocity in water. If the velocity decreases (temperature decreases) with depth, the top part of the wave front moves faster than its bottom part, and gradually the front bends downwards. In the same way, it bends upwards if the sound velocity increases (temperature rises) with depth.

In other words, the ultrasonic wave refracts toward colder water.

Water Depth

100

(m)

0.5 1 1.5 2 Distance (Km)

Here, a fishing ground off Hokkaido island in Japan is taken as an example.

Within 100m

Propagation path

18°

16°

12°

Big Fish School

Water Temp.

Water Depth

100

(m)

small fish

school

0.5 1 1.5 2 Distance (Km)

Seaface

Large difference in density

18°

20°

Water Temp.

18°

Fishing Ground off Hokkaido (Summer)

In summer, there is a large difference in salinity density below and above the 100 m deep point. An ultrasonic wave emitted almost in the horizontal direction propagates within 100 m deep water in the same way as a radio wave in a waveguide. As a result, even a small fish school is sometimes detected at an unexpected long range or on the contrary, detection of a large fish school does not extend to a relatively long range. These phenomena are encountered when two fish schools lie in positions “A” and “B” of the illustration.

The drawing below shows how temperature variation affects sound propagation with respect to different emitting directions (tilt angles).

Beams tilted five and ten degrees bend upward at 400 m and 600 m points respectively. Beams tilted down more than 15 degrees travel in almost straight lines. Between the two beams, a blind zone is created beyond the 600 m point. In this zone nothing can be detected. The shown drawing is only an example calculated by a computer, based on the temperature with depth as shown in the left column of the figure. In actual fishing grounds, the temperature distribution and subsequently the behavior of the sound beam is much more complicated. It is, therefore, for effective use of sonar, necessary to know at least roughly how the temperature is distributed in various waters.

010200

100

150

Sea depth (m)

200 400 600 800 1000

-10

Blind zone

-15

-20

-25

-30

-35

Adverse Effect of Air Bubbles

1200 1400 1600

0 (DEG)

-5

1800

2000

Even infinitesimal air bubbles in sea water (liquid medium) affect propagation of ultrasonic sound. This is because the cubic elasticity of gas is extremely small when compared with that of liquid; the air bubbles violently vibrate (contract and expand) by the action of sound pressure, diffusing the ultrasonic wave and dispersing part of the acoustic energy. In a liquid which contains a large amount of air bubbles, attenuation of an ultrasonic wave increases and the wave is reflected at the boundary of waters which contain and do not contain air bubbles.

From the above it can be said that reflection occurs in the boundary where the density (P) of the material (medium) that is, the velocity of the ultrasonic wave changes. The velocity of an ultrasonic wave with respect to its medium is 200 thru 400 m/s in gas, except for hydrogen and helium; 900 thru 2000 m/s in liquid (several times higher than in air) and 2000 thru 6400 m/s in ordinary metal.

The product of the density (P) and the velocity (C) is called intrinsic acoustic impedance and in the boundary between two media which has extremely different C from each other , most of the acoustic power is reflected and only a small portion penetrates. (In the boundary between water and air, the acoustic energy penetrates with a loss of approximately 30 dB, that is approximately 0.1 % of the energy penetrates from one medium to the other.)

Reflection from water which contains air bubbles is caused by the fact that the cubic elasticity decreases in aerated water, causing the intrinsic acoustic impedance to change.

In the actual sonar operation, adverse effect of air bubbles is shown by interrupted display of target echoes which occurs while crossing over the wake of another boat or when the sonar transducer passes above the air bubbles generated by own ship.

Air bubbles in water have a resonant frequency of l5 kHz thru 100 kHz and hence the ultrasonic wave in this frequency range is most strongly affected.

Reflection at Seabed and Fish School

The nature of the seabed is roughly classified into the following four kinds: crag, sand, mud and seaweeds. In addition, shells and carcass of animals (especially coral) imbedded in the seabed cause reflection loss.

Reflection Loss Lb = 20 log

The actual reflection loss in the sea is shown below. The reflection loss remains almost constant up to 50 kHz and then gradually increases.

Mud Sand

Refelction Loss (dB)

Rock

Frequency (kHz)

Incident sound pressure Reflection sound pressure

(db)

The relation of frequency vs reflection loss for mackerel is shown below. The calculated value and actually measured value nearly coincide. And also, on the contrary to the seabed reflection, the reflection loss decreases as the frequency increases. The “K” in the figure is the coefficient of fish shape, where its larger value introduces smaller reflection loss.

Reflection Loss (dB)

Frequency (kHz)

Reflection Loss (Mackerel No.1)

Species

Sardine Bonito Horse Mackerel Sea Bream Turbot Average

Frequency (kHz)

Reflection Loss (Mackerel No.2)

Incident Direction of Ultrasonic Wave

Back Side Head

1 2 0.13

120.5

0.8-1.2 1.4-2.2 0.4-0.6

0.9 3 0.45 2

120.4

SPECIFICATIONS

1. Display

PPI display on 14" non-glare, high resolution color CRT

2. Display Color

16 colors according to echo strength

3. Numeric information

Scanning Data (Range, Tilt angle, Gain) Trackball Mark Data (Slant range, Horizontal range,

Depth, Bearing)

Range/Bearing Mark Data (Range, Bearing)

4. Range/Pulselength

Range

Basic Range(m)

85 100 150 200 250 300 350 400 450 500 600 800

1000 1200 1600

NOTE:

1. Ranges shown for off-center “on” are maximum.

2. Under certain circumstances, a target (fish school) may not be detected due to its nature or because of sea conditions, even if it is located within the display range.

Maximum Display Range (m)

OFF-Center "OFF" OFF-Center "ON"

110 130 195 260 325 390 455 520 585 650

780 1040 1300 1560 2080

135 160 240 320 400 480 560 640 720 800

960 1280 1600 1920 2560

Pulselength 0.5ms to 20ms, interlocked with range PRR 0.2 sec to 4.0 sec interlocked with range. (can

be changed in 11 steps.)

SP-1

5. AUDIO SEARCH

Searching Method Echoes in the direction of the bearing mark are

audibly monitored by the built-in loudspeaker. Audio Sector 20˚, 40˚, 80˚, 120˚ (selectable) Audio Output 2W Audio Frequency 800Hz

6. Transmitter/Receiver

Transmitter High power MOS FET amplifier with 11-step

power reduction switch Receiver Low noise superheterodyne, continuously scan-

ning beam forming Tx Frequency 55kHz or 68kHz

7. Tilt Angle

Tilt Angle 0˚ to 55˚ Auto Tilt ±2˚ to ±26˚ selectable

8. Hull Unit

400mm travel 600mm travel Transducer T ravel Raising Time

Lowering/Time Driving System

Allowable Ship’s Speed

Remote electric control 18 knots max. (16 knots during raise/lower

operation)

400m 600m 14 sec. 20 sec. 14 sec. 20 sec.

9. Other Features

Interference Rejector, Video Processing, Noise Limiter, Automatic Tilt Scanning Overvoltage Warning, Unretracted Transducer Warning

10. Power Supply, Power Consumption

100/115/200/240VAC, 50/60Hz, 1φ, 0.4kVA on average, 1kVA max. 24/32VDC with optional DC-AC inverter CSH-5050.

SP-2

INDEX

Absorption 59 AGC control 17 Air bubbles 61 Attenuation 59 AUDIO control 21 AUTO TILT key 6

Color test 56 Conti test 55 Control box panel 5

Data description 25 DEMAG button 3 Diagnostics

color test 56 conti test 55 echo-1 test 56 echo-2 test 57 gray test 57 panel test 55 single test 54 SIO test 55 turning on/off 54

Echo-1 test 56 Echo-2 test 57 EVENT DELETE key 6 EVENT key 6

event mark 36 indications 47-50 marks and data 51 menu description 41-43 menu screen 40 MENU-1 41 MENU-2 42 numeric information 35 operation 36–46 own ship mark 36 SCAN menu 43 specifications 35 SYSTEM menu 42 target lock mark 36

IR control 19

Main panel 4 Maintenance

zinc block replacement 53 Mark description 24 MENU key 5 Menu operation

basic 7

scan menu operation 32

system menu description 33

NOISE LIM control 18

OFF-CENTER key 6, 22 Output power 18 Overvoltage remedy 30

F1, F2 keys 22 False echoes (sidelobe) 29 Fish school echo 27

GAIN control 5, 15 Gray test 53

Interface Module CSH-5060 35–51

available menu items 44-46 display marks 35 display mode 35 E/S menu 43

Panel test 55 POWER switch 30 Powering off 11 Powering on 10 Pulselength 17

R/B key 6, 21 Range and bearing measurement 20 RANGE control 5 RANGE switch 11 Refraction 60

Index-1

Scan menu 8 Sea surface reflections 28 Seabed echo 26 SECTOR SCAN key 6, 21 Sidelobe 29 Single test 54 SIO test 51 Sound velocity 58 System configuration 2 System menu 33

Tilt angle

and discriminating fish echoes from bottom 12 for surface fish 13

general selection 11 TILT lever 5, 11 Trackball 5 TRANSDUCER switch 5, 11, 30 TVG adjustment 16 TX cycle 19

Wake recognition 28

Index-2

Furuno CSH-5 MARK-2 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

SAFETY INSTRUCTIONS

TABLE OF CONTENTS

1. FOREWORD

2. SYSTEM CONFIGURATION

Operating Controls

3. CONTROLS

Main Panel

Control Box Panel

Menu Screen

General

4. BASIC OPERATION

Turning the Power On/Off

Lowering the Transducer

Selecting a Display Range

Setting the T ilt Angle

Adjusting the Gain

5. FINE TUNING THE PICTURE

General

Eliminating Unwanted Feeble Echoes

Displaying Surface Fish Clearly

Suppressing Seabed Tail

Suppressing Seabed and Sea Surface Reflections in Shallow Fishing Grounds

Rejecting Sonar Interference and Noise

Selecting Horizontal Beamwidth

Selecting Vertical Beamwidth

6. ADV ANCED OPERA TION

General

Measuring Range and Bearing to a Target

Detecting Fish Schools Aurally

Relocating Fish School for Easy Observation

Finding Fish School Center

Registering F1/F2 (function) key and Recalling

7. MARK AND DATA

Marks

Data

8. INTERPRETING THE DISPLAY

General

Interpreting the Display

Overvoltage W arning

Unretracted Transducer Warning

9. WARNING

General

Changing Menu Settings

10. MENU

11. INTERFACE MODULE CSH-5060

Specifications

Operation

Indications

Marks and Data

Event Mark Position Output

General

12. MAINTENANCE

13. UNIT DIAGNOSTIC TESTS

Description of Unit-diagnostic Tests

14. CHARACTERISTICS OF THE ULTRASONIC WAVE IN W ATER

Sound Velocity

Absorption and Attenuation

Refraction

Adverse Effect of Air Bubbles

Reflection at Seabed and Fish School

SPECIFICATIONS

INDEX