JMA-2343/2344 - ProNav

JMA-2343/2344

はじめに 

このたびは、JRC 船舶レーダJMA-2343/JMA-2344をお買い上げいただきま 

して、まことにありがとうございます。 

本装置は、レーダ信号の送受信部、ブラウン管表示部および空中線等の主要部か 

らなる、船舶の安全航行を図るための船舶用レーダ装置です。 

● お使いになる前に、この取扱説明書をよくお読みのうえ、正しくお使いくだ 

さい。 

● 取扱説明書は必要なときに参照できるよう大切に保管してください。 

万一、ご使用中にわからないことや不具合が生じたときにお役立てください。 

PREFACE 

Thank you very much for purchasing the JRC marine radar equipment, 

JMA-2343 and JMA-2344. 

This equipment is a marine radar equipment designed to obtain safe 

operation of marine ships. The equipment consists of a radar signal 

transceiver unit, a CRT display unit and a scanner unit as its main units. 

● Before operating the equipment, be sure to read this instruction manual 

carefully for correct operation. 

● Maintain this instruction manual so that operators can refer to it at 

anytime. 

Refer to this manual when any inconvenience or defect occur. 

I

Pictorial Indication 

●Before Operation● 

Various pictorial indications are included in this manual and are shown 

on these equipment so that you can operate them safely and correctly 

and prevent any danger to you and / or to other persons and any damage 

to your property during operation. Such indications and their meanings 

are as follows. 

Please understand them before you read this manual: 

WARNING 

This indication is shown where any person is supposed to be in danger of 

being killed or seriously injured if this indication is neglected and these 

equipment are not operated correctly. 

CAUTION 

This indication is shown where any person is supposed to be injured or any 

property damage is supposed to occur if this indication is neglected and these 

equipment are not operated correctly. 

Examples of pictorial indication 

Disassembling 

Prohibited 

Disconnect the 

power plug 

Electric 

Shock 

Prohibition 

instruction 

The△mark represents CAUTION (including DANGER and WARNING). 

Detailed contents of CAUTION ("Electric Shock" in the example on the 

left.) is shown in the mark. 

The mark represents prohibition. 

Detailed contents of the prohibited action ("Disassembling Prohibited" in 

the example on the left) is shown in the mark. 

The ● mark represents instruction. 

Detailed contents of the instruction ("Disconnect the power plug" in the 

example on the left) is shown in the mark. 

Warning label 

There is a warning label on the top cover of the equipment. 

Do not try to remove, break or modify the label. 

III

●ご使用上の注意 ● 

警告 

空中線、送受信機及び指示機の内部には触れないでください。 

高電圧部により感電の原因となります。機器内部の保守、点検、調整等は当社の営 

業部またはお近くの支社・支店・営業所または代理店にサービスを依頼してくださ 

い。 

当社の営業部・支社・支店・営業所 

巻末の「事業所一覧」をご覧ください。 

空中線輻射部は回転しますので、近づかないでください。 

急に空中線が回転し人体を殴打して、負傷する原因となります。 

空中線輻射部は人が近づけないよう操舵室の屋根、フライングブリンジ、架台、レ 

ーダーマスト等の高い場所に設置することをおすすめします。また、人の近づく恐 

れのある場合は空中線ガードを設置することをおすすめします。空中線の作業をす 

る場合は、空中線の安全スイッチを切ってください。 

空中線は人の頭より高い位置に設置してください。 

至近距離で直接電波を浴びると人体に影響を及ぼす原因となります。 

保守、点検で人がアンテナに接近する場合は指示機の準備 / 断スイッチを 

押し、指示機を準備状態にしてください。 

至近距離で直接電波を浴びると人体に影響を及ぼす原因となります。 

注意 

レーダはあくまでも航法援助装置としてご使用ください。 

また、操船の最終判断は必ず操船者自身で行ってください。 

操船の最終判断を、レーダが表示する情報のみに頼った場合、衝突、座礁等の事故の 

原因となることがあります。 

IV

●Cautions to be used during operation● 

WARNING 

Do not touch the insides of the scanner unit, transceiver and display 

unit. 

Touching any high voltage area, you will get an electric shock. For 

maintenance, inspection and adjustment of internal parts of these equipment, 

consult with our sales office or distributor in your district. 

Since the scanner unit radiator rotates, do not approach it. 

The scanner unit may start rotating suddenly, and consequently any person may 

be struck and be injured. We recommend you to install the scanner unit 

radiator on the roof of the wheel house, flying bridge, trestle, radar mast or any 

other high position so that no person can approach it. When servicing the 

scanner unit, set the scanner unit safety button to the OFF position. 

Install the scanner unit at any place higher than any person. 

If being exposed directly to electric wave at close range, you may suffer adverse 

influence. 

When approaching the antenna for maintenance or inspection, set 

the power button of the display unit to the ST-BY position. 

If being exposed directly to electric wave at close range, you may suffer adverse 

influence. 

CAUTION 

Use these radar only as assisting devices for navigation. 

Also, the officer should make the final decision for maneuvering by 

himself. 

If you make the final decision of maneuvering only on the information which a 

radar display, it may become the cause of accidents, such as collision and 

stranding. 

V

──ご使用前に注意していただきたい 

いただきたいこと 

こと── 

高電圧に対する注意 

無線装置、レーダなどの電子機器の内部には数百から数万ボルトの高電圧が使用されていま 

す。通常の操作においてはまったく危険はありませんが、万一、誤って機器内部に触れた場 

合非常な危険を伴います。( 専門整備員以外の機器内部の保守・点検・調整は禁止 ) 

数万ボルトの高圧では感電即死の危険が大きく、また時により数百ボルトの電圧でも感電死 

することがあります。このような危険を防止するには機器の内部に手を入れるとき、必ず電 

源スイッチを切って、一端を確実に接地した電源でコンデンサーなどを放電させ、電気の残 

っていないことを確めた上で初めて手を内部に入れるようにしてください。この際、乾燥し 

た木綿の手袋などを用いればなおいっそう危険防止となります。また左手をポケットに入れ、 

両手を同時に用いないことも必要な注意の一つです。感電したときの障害は二次的に大きく 

なることがあるので足場もしっかりした所を選ぶことが大切です。感電したときは火傷した 

所を完全に消毒して、手当を速やかに行うことが必要です。 

電撃の救出上の注意 

電撃を受けた人を発見した場合、直ちに電源を切り回路を接地してください。回路が直ちに 

切れないときは、感電した人をできるだけ早く乾いた板、布などの絶縁物を介して直接感電 

した人に触れずに離してください。 

感電したとき、頭脳の呼吸中枢に電流が流れると呼吸が急に止まります。衝撃があまりひど 

くないときは人工呼吸を行うことにより呼吸を回復します。電撃を受けた人は非常に顔色が 

悪くなり、脈が大変弱くなってしまうか、まったく止まってしまうことがあり、人事不省に 

なり硬直します。 

VI

──PRECAUTIONS BEFORE OPERATION── 

Cautions for high voltage 

High voltages from hundreds volts to tens of thousands volts are to be applied to the 

electronic equipment such radio and radar devices. You do not face any danger during 

normal operation, but sufficient cares are required for maintenance, inspection and 

adjustment of their internal components. (Authorized maintenance personnel alone are 

permitted to implement maintenance, check-ups or adjustment of internal components.) 

High voltages of tens of thousands volts are so dangerous as to bring an instantaneous 

death from electric shock, but even voltages of hundreds volts may sometimes lead to a 

death from electric shock. To prevent such an accident, make it a rule to turn off the 

power button, discharge capacitors with a wire surely earthed on an end and make sure 

that internal parts are no longer charged before you touch any parts inside these devices. 

At the time, wearing dry cotton gloves ensures you further to prevent such danger. It is 

also a necessary caution to put one of your hands in the pocket and not to use your both 

hands at the same time. 

It is also important to select a stable foothold always to prevent additional injuries once 

you were shocked by electricity. If you were injured from electric shock, disinfect the 

burn sufficiently and get it taken care of promptly. 

What to do in case of electric shock 

When finding a victim of electric shock, turn off the power source and earth the circuit 

immediately. If it is impossible to turn off the circuit, move the victim away promptly 

using insulators such as dry wood plate and cloth without touching the victim directly. 

In case of electric shock, breathing may stop suddenly if current flows to the respiration 

center in the brain. If the shock is not so strong, artificial respiration may recover 

breathing. When shocked by electricity, the victim will come to look very bad with weak 

pulse or without beating, resulting in unconsciousness and rigidity. 

VII

FIRST AID TREATMENTS 

☆ First-aid treatments 

As far as the victim of electric shock is not in dangerous condition, do not move him and practice 

artificial respiration on him immediately. Once started, it should be continued rhythmically. 

(1) Do not touch the victim confusedly as a result of the accident, but the rescuer may also get 

an electric shock. 

(2) Turn off the power source calmly and certainly and move the victim away quietly from the 

electric line. 

(3) Call a physician or ambulance immediately or ask someone to call a doctor. 

(4) Lay the victim on his back and loosen his necktie, clothes, belt, etc. 

(5) a. Examine the victim's pulse. 

b. Examine his heartbeat bringing your ear close to his heart. 

c. Examine his breathing bringing the back of your hand or your face close 

d. Check the size of the pupils of his eyes 

(6) Open the victim's mouth and take out artificial teeth, cigarette or chewing gum if any. 

Keep his mouth open, stretch his tongue and insert a towel or the like in his mouth to 

prevent the tongue from suffocating. (If it is hard to open his mouth due to set teeth, open it 

with a screwdriver and insert a towel in this mouth.) 

(7) Then, close his mouth so that foaming mucus does not accumulate inside. 

IX

☆When pulse is beating but breathing has stopped 

(1) Tilt the victim's head back as far as this face looks back. (A pillow may be inserted under his 

neck.) 

(2) Push his jaw upward to open his throat wide (to spread his airway). 

(3) Pinch the victim's nostrils and take a deep breath, block his mouth completely with yours 

and blow into his mouth strongly. Take a deep breath again and blow into his mouth. 

Continue this 10 to 15 times a minute (blocking his nostrils). 

(4) Carefully watch that he has recovered his natural breathing and stop practicing artificial 

respiration. 

(5) If it is difficult to open the victim's mouth, insert a rubber or vinyl tube into one of his 

nostrils and blow into it blocking the other nostril and his mouth completely. 

(6) When the victim recovers consciousness, he may try to stand up suddenly, but let him lie 

calmly and serve him with a cup of hot coffee or tea to keep him warm and quiet. (Never give 

him alcoholic drinks.) 

Method of mouth-to-mouth respiration by raising head 

1 (1) Raise the victim's head. Support his 

forehead with one of your hand and his 

neck with the other hand. → 1 

When you tilt his head backward, the 

victim, in most cases, opens his mouth to 

the air. This makes mouth-to-mouth 

respiration easy. 

2 

(2) Cover his mouth as widely as possible 

with yours and press your cheek against 

his nose → 2 , or, pinch his nostrils 

with your fingers to prevent air from 

leaking. → 3 

3 

(3) Blow into his lungs. 

Continue blowing into his mouth until his 

breast swells. Blow into his mouth as 

quickly as possible for the first 10 times. 

Fig.1 Mouth-to-mouth respiration 

XI

☆When both pulse and breathing have stopped 

When no pulse has come not to be felt, his pupils are open and no heartbeat is heard, cardiac 

arrest is supposed to have occurred and artificial respiration must be performed. 

(1) Place your both hands, one hand on the other, on the lower one third area of his breastbone 

and compress his breast with your elbows applying your weight on his breast so that it is 

dented about 2cm (repeat compressing his breast 50 times or so a minute). 

(Cardiac massage) 

(2) In case of one rescuer, 

Repeat cardiac massages about 15 times and blow into his mouth 2 times quickly, and repeat 

this combination. 

In case of two rescuers, 

One person repeats cardiac massages 5 times while the other person blows into his mouth 

once, and they shall repeat this combination. 

(Cardiac massage and mouth-to-mouth respiration) 

(3) Examine his pupils and his pulse sometimes. When the both have returned to normal, stop 

the artificial respiration, serve him with a cup of coffee or tea and keep him warm and calm 

while watching him carefully. Commit the victim to a medial specialist depending on his 

condition. To let him recover from the mental shock, it is necessary for persons concerned to 

understand his situations and the necessary treatments. 

1 

2 

3 

4 

Fig.2 Cardiac massage 

XIII

機器外観 

EQUIPMENT APPEARANCE 

NKE-249 形空中線 

Scanner unit Type NKE-249 

NKE-250 形空中線 

Scanner unit Type NKE-250 

NCD-4170 形指示機 

Display Unit Type NCD-4170 

XIV

JMA- 2343 

2344 

INSTRUCTION MANUAL 

[English edition]

Contents 

PREFACE ······························································································································I 

Before Operation··················································································································III 

Cautions to be used during operation·················································································· V 

PRECAUTIONS BEFORE OPERATION·········································································· VII 

Cautions for high voltage································································································ VII 

What to do in case of electric shock ·············································································· VII 

FIRST AID TREATMENTS································································································· IX 

☆First-aid treatments······································································································ IX 

☆When pulse is beating but breathing has stopped······················································ XI 

☆When both pulse and breathing have stopped ························································· XIII 

EQUIPMENT APPEARANCE ··························································································XIV 

Glossary of Radar Terms································································································· 144 

Chapter 1 Introduction······························································· 145 

1.1 Function ·········································································································································145 

1.2 Features·········································································································································145 

1.3 Composition···································································································································146 

1.4 Configuration··································································································································147 

1.5 General System Diagram ·············································································································150 

Chapter 2 Names and Functions of Control Panel Parts 

and Menu Composition ············································ 152 

2.1 Functions of the Front Control Panel Keys··················································································152 

2.1.1 Functions of the front control panel keys ·············································································152 

2.1.2 Composition and functions of the soft key switches····························································153 

2.1.3 Functions of the cross key ····································································································154 

2.2 Explanation of Screen Readout····································································································156 

2.3 Explanation of Functions within the Menu ···················································································158 

2.3.1 Menu Composition ················································································································158 

2.3.2 Functions within the menu ····································································································160 

Chapter 3 Basic Operations ······················································ 164 

3.1 Flow of Operations ························································································································164 

Soft key operation ···························································································································165 

3.1.1 Turning the power ON and starting the system···································································166 

1. Turning the power ON···············································································································166 

136

2. Undertake transmission ············································································································166 

3.1.2 Tuning operation····················································································································166 

3.1.3 Adjusting monitoring and image ···························································································167 

3.1.4 Data acquisition and monitoring ···························································································167 

3.1.5 Ending the operation and shutting down the system ··························································167 

1. Interrupting the transmission ····································································································167 

2. Shutting the power off ···············································································································167 

3.2 Monitoring Standby ·······················································································································168 

3.2.1 Changing the brightness of the screen ················································································168 

3.2.2 Changing the brightness of the control panel lighting ·························································168 

3.2.3 Switching among display languages····················································································168 

3.2.4 Setting the buzzer volume ····································································································168 

3.3 Basic Operations ···························································································································169 

3.3.1 Transmitting ···························································································································169 

3.3.2 Interrupting transmission·······································································································169 

3.3.3 Changing the range (scale of distance) ···············································································169 

3.3.4 Erasing and displaying the fixed range ring·········································································169 

3.3.5 Erasing ship's heading marker ·····························································································170 

3.3.6 Adjusting the tuning···············································································································171 

3.3.7 Adjusting the sensitivity·········································································································171 

3.3.8 Eradicating radar interference ······························································································172 

3.3.9 In the event of rain or snow···································································································173 

3.3.10 In case of high waves············································································································174 

3.3.11 Measuring the range to the target ························································································175 

1. Using VRM·································································································································175 

Measuring the distance from the ship using #1VRM ······························································175 

Setting whether or not use of #2VRM is enabled····································································175 

Operating the #1VRM/#2VRM ·································································································175 

Erasing the #1VRM and #2VRM······························································································176 

2. Moving the center of the VRM··································································································176 

3. Changing the interval between the parallel line cursors ·························································176 

4. Using the cross hair cursor·······································································································176 

3.3.12 Changing the range unit········································································································177 

3.3.13 Measuring the bearing of a target·························································································177 

1. Using EBL··································································································································178 

Measuring the distance from the ship using #1EBL································································178 

Setting whether or not use of #2EBL is enabled·····································································178 

Operating the #1VRM/#2VRM ·································································································178 

Erasing the #1EBL and #2EBL ································································································179 

2. Moving the center of the EBL ···································································································179 

137

3. Changing the interval between the parallel line cursors ·························································179 

4. Using the cross hair cursor·······································································································179 

3.3.14 Floating VRM and EBL ·········································································································180 

Setting the #1EBL and #1VRM to enable moving ········································································180 

Setting the point of reference and center position·········································································180 

Operating the EBL and VRM··········································································································180 

Canceling the point of reference or center position·······································································180 

3.3.15 Using the parallel line cursor·································································································181 

The parallel line cursor function is set to #1EBL and #1VRM······················································181 

Operating the parallel line cursor ···································································································181 

Canceling the parallel line cursor ···································································································181 

3.3.16 Switching the EBL and cursor bearing display among relative, true 

and magnetic bearing display mode·····················································································181 

Selection of bearing criteria (magnetic bearing, gyrocompass bearing)······································183 

Selection of the bearing criteria······································································································183 

3.3.17 Changing the bearing display method of the PPI screen ···················································183 

Course setting in course-up mode·································································································185 

3.3.18 Simultaneously measuring the bearing, distance and travel time to the target·················185 

Displaying cursor·····························································································································186 

Moving the cursor····························································································································186 

Erasing the cursor ···························································································································186 

3.3.19 L/L display of the cursor········································································································187 

3.3.20 Magnifying the echo images on the PPI screen··································································187 

1. Using the image expansion function························································································187 

2. Changing the transmission pulse width ···················································································188 

3. Using the zoom function ···········································································································189 

Setting the zoom area···············································································································189 

Canceling the zoom ··················································································································190 

3.3.21 Reducing unnecessary noise and emphasizing the target·················································190 

Set the image processing ···············································································································190 

Canceling image processing ··········································································································191 

3.3.22 Moving the center of the PPI screen····················································································191 

Setting the position to which the center is relocated.····································································191 

Canceling center relocation ············································································································192 

3.3.23 Controlling power consumption of the radar········································································192 

Setting the transmission time ·········································································································192 

Setting the standby time ·················································································································192 

Commencing timed transmission···································································································192 

Canceling timed transmission ········································································································193 

Canceling timed transmission while in standby mode ··································································193 

138

3.3.24 Locking a fixed target on the radar PPI screen while the ship is navigating······················194 

Commencing True Motion display ·································································································194 

Canceling true motion display ········································································································195 

3.3.25 Monitoring the motion of other ships (Targets)····································································197 

1. Radar display of wake···············································································································197 

Commencing radar display of a wake······················································································197 

Ending radar display of a wake ································································································197 

2. Using the lookout alarm ············································································································197 

Setting the guard zone··············································································································197 

Changing the alarm mode ········································································································199 

Eradicating the guard zone·······································································································199 

Calling a guard zone ·················································································································199 

Changing the sensitivity of the alarm ·······················································································199 

3.4 Other Convenient Functions·········································································································200 

3.4.1 Displaying the ship's speed on the display unit ···································································200 

3.4.2 Displaying the ship's heading on the display unit································································200 

3.4.3 Displaying position information (latitude/longitude, LORAN C time difference) 

of the ship and waypoint information (latitude/longitude)·····················································201 

Display of position information··································································································201 

Erasing location information ·····································································································201 

3.4.4 Displaying the waypoint ········································································································202 

Display of the waypoint·············································································································202 

Erasing the waypoint·················································································································202 

3.5 Miscellaneous Considerations······································································································203 

3.5.1 Replacing the battery (BT1)··································································································203 

3.5.2 In cases of abnormality during operations ···········································································204 

3.6 External Navigation Devices·········································································································205 

3.6.1 Obtaining information on bearing ·························································································205 

3.6.2 Obtaining information on speed····························································································205 

3.6.3 Obtaining information on position·························································································205 

3.6.4 Obtaining information on distance to the waypoint······························································206 

Chapter 4 How to Interpret the PPI Screen ······························ 207 

4.1 Height of and the Distance to the Target ·····················································································207 

4.2 Returns from a Target···················································································································208 

4.3 Propagation Path of Radio Waves·······························································································208 

4.3.1 Sea returns ····························································································································209 

4.3.2 False echoes ·························································································································209 

4.4 Display of Radar Transponder······································································································211 

139

Chapter 5 Maintenance and Inspection ···································· 212 

5.1 General Maintenance····················································································································212 

5.2 Scanner Unit··································································································································213 

5.3 Display Unit····································································································································213 

5.4 Special Parts··································································································································214 

5.5 Circuit Blocks for Repair················································································································214 

5.6 Actions to Deal with Abnormalities and Breakdown····································································216 

Chapter 6 After-sales Service ··················································· 218 

Chapter 7 Disposal···································································· 220 

7.1 Equipment Disposal ······················································································································220 

7.2 Disposal of Used Batteries············································································································220 

7.3 Disposal of Used Magnetron ········································································································220 

Chapter 8 Specifications···························································· 221 

8.1 General ··········································································································································221 

8.2 Scanner Unit (NKE-249/250)········································································································222 

8.3 Display Unit (NCD-4170) ··············································································································224 

8.4 Rectifier Unit (NBA-797A)·············································································································228 

8.5 Unit-to-unit Spacing·······················································································································228 

Chapter 9 Installation································································· 229 

9.1 General ··········································································································································229 

9.2 Installing the Scanner Unit············································································································230 

9.2.1 Selecting the installation location··························································································230 

9.2.2 Installation procedure············································································································230 

9.2.3 Connection of cables to be assembled················································································233 

9.3 Installing the Display Unit··············································································································236 

9.3.1 Selecting the installation location··························································································236 

9.3.2 Installation procedure············································································································236 

9.3.3 Connecting the power cable ·································································································236 

9.3.4 Display unit rear panel···········································································································237 

9.3.5 Connection of the external buzzer························································································238 

9.3.6 Connecting an electromagnetic compass············································································240 

9.4 Modifications to be Made to the Inboard Power Supply ·····························································241 

1. Display unit ································································································································241 

2. Scanner unit·······························································································································241 

9.5 Cable Assemblies··························································································································242 

9.5.1 Inter-unit cable (CFQ6774-10/15/20, CFQ6882-10/15/20)·················································242 

140

9.5.2 Power cable (CFQ-6776)······································································································243 

9.5.3 Selecting a long cable ···········································································································243 

9.6 After-installation Adjustments ·······································································································244 

9.6.1 Installation-time check···········································································································244 

9.6.2 Functional checks··················································································································244 

9.6.3 Adjustment items···················································································································244 

9.6.4 Rectifier unit ···························································································································245 

9.7 Adjustment Procedures·················································································································246 

9.7.1 General adjustments·············································································································246 

1. Adjustments to be made when a part is replaced···································································246 

2. CRT monitor off center adjustment ··························································································246 

3. Adjusting the brilliance level of the CRT monitor screen. ·······················································246 

4. Adjusting the focus of the CRT monitor screen·······································································246 

9.7.2 Adjusting the scanner unit·····································································································247 

1. Adjusting the AVR output voltage from the modulator····························································247 

2. Adjusting the tuning indicator level of the receiver ··································································247 

9.7.3 Adjusting the display unit ······································································································247 

1. Adjusting the brilliance level······································································································247 

2. Adjusting the focus of the CRT monitor screen·······································································247 

3. Adjusting the tilt angle of the display unit·················································································248 

4. Adjusting the CRT display ········································································································248 

5. Adjusting the AVR output voltage ····························································································248 

9.8 Initial Settings·································································································································249 

9.8.1 Adjustment of the receiver ····································································································250 

1. Tune preset································································································································250 

2. Adjusting the central frequency ································································································251 

3. Adjusting the level of the tune level indicator···········································································251 

9.8.2 Adjusting the noise level ·······································································································252 

9.8.3 Adjusting the bearing·············································································································252 

9.8.4 0 NM adjustment (Initial setting of distance)········································································253 

9.8.5 Setting the antenna height····································································································254 

9.8.6 Presetting the sensitivity········································································································255 

9.8.7 Presetting the sea clutter ······································································································255 

9.8.8 Suppression of main bang····································································································256 

9.8.9 Display of simulator image····································································································257 

9.8.10 Setting the TD reception number ·························································································258 

9.8.11 GPS/DGPS····························································································································259 

1. Initial setting of GPS····················································································································259 

2. Initial setting of DGPS·················································································································259 

3. Status of reception of GPS and DGPS······················································································260 

141

9.9 Returning to the Initial Setting Conditions····················································································264 

9.10 Maintenance ··································································································································265 

9.10.1 General maintenance············································································································265 

1. Cleaning·····································································································································265 

2. Screw inspection ·······················································································································265 

3. Cabling check ····························································································································265 

9.10.2 Scanner unit···························································································································266 

1. Radiation unit·····························································································································266 

2. Rotary drive block (JMA-2344)·································································································267 

9.10.3 Display unit·····························································································································268 

Cleaning the Display Unit Screen ··································································································268 

142

Attached Figures 

【Fig. 101 INTERCONNECTION DIAGRAM OF JMA-2343】 

【Fig. 102 INTERCONNECTION DIAGRAM OF JMA-2344】 

【Fig. 103 POWER SUPPLY DIAGRAM OF JMA-2343】 

【Fig. 104 POWER SUPPLY DIAGRAM OF JMA-2344】 

【Fig. 105 INTERNAL CONNECTIONS OF SCANNER UNIT NKE-249】 

【Fig. 106 INTERNAL CONNECTIONS OF SCANNER UNIT NKE-250】 

【Fig. 107 CIRCUIT DRAWING OF MODULATOR UNIT CME-307】 

【Fig. 108-1 CIRCUIT DRAWING OF RECEIVER UNIT CAE-457 (1/2)】 

【Fig. 108-2 CIRCUIT DRAWING OF RECEIVER UNIT CAE-457 (2/2)】 

【Fig. 109 CIRCUIT DRAWING OF MODULATOR UNIT CME-308】 

【Fig. 110-1 CIRCUIT DRAWING OF RECEIVER UNIT CAE-457-1 (1/2)】 

【Fig. 110-2 CIRCUIT DRAWING OF RECEIVER UNIT CAE-457-1 (2/2)】 

【Fig. 111 INTERNAL CONNECTIONS OF DISPLAY UNIT NCD-4170】 

【Fig. 112-1 CIRCUIT DRAWING OF MAIN CONTROL UNIT CMC-1156 (1/4)】 




【Fig. 113 CIRCUIT DRAWING OF SOFT KEY PANEL UNIT CCK-872】 

【Fig. 114 CIRCUIT DRAWING OF MAIN PANEL UNIT CCK-873】 

【Fig. 115 CIRCUIT DRAWING OF POWER SUPPLY UNIT CBD-1596】 

【Fig. 116 CIRCUIT DRAWING OF CRT MONITOR UNIT】 

【Fig. 117 BLOCK DIAGRAM OF SCANNER UNIT】 

【Fig. 118 BLOCK DIAGRAM OF DISPLAY UNIT】 

143

Glossary of Radar Terms 

A/D 

ACQ 

A-SEA 

A-RAIN 

A-TUNE 

CPU 

CRT 

CUP 

EBL 

EXP 

FTC 

GPS 

HUP 

IR 

L/L 

MARPA 

MH 

MOB 

NM 

NUP 

PCB 

PPI 

PROCESS 

PW 

RR 

RM 

SHM 

STBY 

STC 

TD 

TM 

TI 

VCT 

VD 

VRM 

WPT 

X-MIT 

Analog to Digital conversion 

Acquisition 

Automatic Sea surface clutter suppression 

Automatic Rain and snow clutter suppression 

Automatic Tuning 

Central Processing Unit 

Cathode-ray Tube 

Course-Up 

Electronic Bearing Line 

Expansion 

Fast Time Constant, also known as Rain and snow clutter suppression 

Global Positioning System 

Head-Up 

Interference Rejection 

Latitude/Longitude 

Mini Automatic Radar Plotting Aid 

Modulator High Voltage 

Man Over Board 

Nautical Mile 

North-Up 

Printed Circuit Board 

Plan Position Indicator 

Process 

Pulse Width 

Range Rings (Fixed) 

Relative Motion 

Ship’s Heading Marker 

Standby 

Sensitivity time control, also known as Sea surface clutter suppression 

Time Difference 

True Motion 

Trigger 

Vector 

Video 

Variable Range Marker 

Waypoint 

Transmit 

144

1 Introduction 

1.1 Function 

The JMA-2243/2344 series radar devices are marine radar devices that use scanner units 

including transmitter and receiver and 10 inch monochrome cathode-ray tube utilizing the 

compact raster scan method for achieving a fully semi-conductor adopted (excluding special 

electron tubes) system. 

This equipment comprises radar as defined in the Wireless Telegraphy Act. 

1.2 Features 

Enhanced fundamental performance of the radar 

Through switching among 4 steps in terms of pulse width/cycle switching of frequency and 

switching among 3 steps in receiver bandwidth, enhanced fundamental performance of the 

radar has been achieved towards display of clearer and higher quality images. Moreover, 

through the incorporation of advanced digital signal processing, performance in target detection 

during increment weather has been improved. 

Confirmation of the ship's position and identifying the waypoint at a glance 

Through connecting to navigation equipment such as GPS, the location of the ship (numerical 

value) or a mark on the waypoint may be displayed on the screen and through this, 

the difference between the bearing of the waypoint and the ship's heading may be grasped 

at a glance. 

High operability 

EBL and VRM that are frequently used are equipped with dedicated switches. Moreover, 

4 soft key switches have been incorporated and functions that are relatively frequently used 

may be operated with ease. Additionally, a system for selecting functions that are infrequently 

used from the menu has been adopted. 

145

1.3 Composition 

Composition of the Radar and Ship Internal Power Source 

Comprehensive type Scanner unit Display unit Ship internal power source 

JMA-2343 


NKE-249 

NKE-250 

NCD-4170 

DC (12V/24V/32V) 

or 

AC (Note) (100V/110V/115V/ 

200V/220V/230V) 

50/60Hz single phase 

Rectifier type (option) 

NBA-797A 

(Note) When AC power source is used, the optional rectifier is required. 

Accessories 

Product Name Quantity JRC Code Remarks 

Instruction Manual 1 7ZPRD0558 This manual 

Cable between the scanner 

CFQ6774-15 10 core composite cable 

unit and display unit 

(JMA-2343) 15m 

1 



Power cable assembly 1 CFQ-6776 2m 

Sun shield 1 MTV303344 - 

Standard spare parts kit (7ZXRD0008) 

Product name (type) Quantity JRC Code Remarks 

Fuse (SB3.15) 2 5ZFAD00382 (for 24/32V) 3.15A 

Fuse (SB6.3) 3 5ZFAD00540 (for 12V) 6.3A 

Fuse (SB5) 2 5ZFAD00364 (for 24/32V) 5A 

Fuse (SB10) 3 5ZFAD00539 (for 12V) 10A 

Optional 

Product Name Quantity JRC Code Remarks 

Cable between the scanner 

unit and display unit 

CFQ6774-10 

(JMA-2343) 

10 core composite cable 

10m 


1 




CFQ6882-20 

(JMA-2344) 

14 core composite cable 

20m 

146

1.4 Configuration 

Fig. 1.1 OUTLINE DRAWING OF SCANNER UNIT NKE-249 

147

Fig. 1.2 OUTLINE DRAWING OF SCANNER UNIT NKE-250 

148

Fig. 1.3 OUTLINE DRAWING OF DISPLAY UNIT NCD-4170 

149

1.5 General System Diagram 

SCANNER UNIT NKE-249 

空中線 NKE-249 

10-CORES COMPOSITE CABLE 

10 芯シールド付複合ケーブル 

JRC SUPPLY:CFQ6774-15 12.0φ(max) 

CFQ6774-15 最大 12.0φ(JRC 支給 ) 

DISPLAY UNIT NCD-4170 

指示機 NCD-4170 

250V-TTYCYS-1 

250V-TTYCYS-1 

250V-TTYCYS-1 

250V-TTYCYS-1 

CFQ-6776(2m) 8.0φ(max) (JRC SUPPLY) 

CFQ-6776(2m) 最大 8.0φ (JRC 支給 ) 

GPS 

COMPASS 

NMEA 

REMOTE MONITOR 

SHIP'S MAIN( 船内電源 ) 

DC 10.8~42V 

NOTES: 

ELIMINATING THE INTERFERENCE ON FREQUENCIES USED FOR MARINE COMMUNICATIONS 

AND NAVIGATION DUE TO OPERATION OF THE RADAR. 

ALL CABLES OF THE RADAR ARE TO BE RUN AWAY FROM THE CABLES OF RADIO EQUIPMENT. 

(EX. RADIOTELEPHONE.COMMUNICAITONS RECEIVER AND DIRRECTION FINDER.ETC.) 

ESPECIALLY INTER-WIRING CABLES BETWEEN SCANNER UNIT AND DISPLAY UNIT OF THE 

RADAR SHOULD NOT BE RUN PARALLEL WITH THE CABLES OF RADIO EQUIPMENT. 

ご注意 

レーダの動作が他の無線装置に、雑音妨害を与えることを防止するために、レーダケーブル、 

特に空中線ケーブルを他の無線装置のケーブルと平行に設置しないでください。 

Fig. 1.4 GENERAL SYSTEM DIAGRAM OF JMA-2343 

150

SCANNER UNIT NKE-250 

空中線 NKE-250 

14-CORES COMPOSITE CABLE 

14 芯シールド付複合ケーブル 

JRC SUPPLY:CFQ6882-15 12.0φ(max) 

CFQ6882-15 最大 12.0φ(JRC 支給 ) 

DISPLAY UNIT NCD-4170 

指示機 NCD-4170 

250V-TTYCYS-1 

250V-TTYCYS-1 

250V-TTYCYS-1 

250V-TTYCYS-1 

CFQ-6776(2m) 8.0φ(max) (JRC SUPPLY) 

CFQ-6776(2m) 最大 8.0φ (JRC 支給 ) 

GPS 

COMPASS 

NMEA 

REMOTE MONITOR 

SHIP'S MAIN( 船内電源 ) 

DC 10.8~42V 

NOTES: 

ELIMINATING THE INTERFERENCE ON FREQUENCIES USED FOR MARINE COMMUNICATIONS 

AND NAVIGATION DUE TO OPERATION OF THE RADAR. 

ALL CABLES OF THE RADAR ARE TO BE RUN AWAY FROM THE CABLES OF RADIO EQUIPMENT. 

(EX. RADIOTELEPHONE.COMMUNICAITONS RECEIVER AND DIRRECTION FINDER.ETC.) 

ESPECIALLY INTER-WIRING CABLES BETWEEN SCANNER UNIT AND DISPLAY UNIT OF THE 

RADAR SHOULD NOT BE RUN PARALLEL WITH THE CABLES OF RADIO EQUIPMENT. 

ご注意 

レーダの動作が他の無線装置に、雑音妨害を与えることを防止するために、レーダケーブル、 

特に空中線ケーブルを他の無線装置のケーブルと平行に設置しないでください。 

Fig. 1.5 GENERAL SYSTEM DIAGRAM OF JMA-2344 

151

2 Names and Functions of Control Panel Parts 

and Menu Composition 

2.1 Functions of the Front Control Panel Keys 

Normal operations with respect to this radar equipment may be undertaken from the front 

panel of the display. Moreover, by using functions that are defined by the menu, the operator 

may make full use of the functions of this equipment. 

While the operations are simple, in order to display the necessary information on the 

cathode-ray tube, it is important that the operator has full understanding of the functions of 

the various operations. 

2.1.1 Functions of the front control panel keys 

Open a menu 

Various settings 

Cross key 

Tune adjustment 

Range 

Sensitivity 

adjustment 

Sea surface 

clutter suppression 

EBL 

VRM 

Brilliance/ 

Ship’s head line off 

Rain and snow 

clutter suppression 

Transmit/Off 

Stand-by/Off 

Soft key 1 Soft key 4 

Soft key 2 

Soft key 3 

152

2.1.2 Composition and functions of the soft key switches 

In order to simplify operations, this equipment is equipped with 4 soft key switches on the 

front panel. The optional items corresponding to each soft key is displayed at the lowermost 

part of the screen and the function may be executed by pushing the corresponding key. 

The soft key menu is comprised as follows. 

Key1 

DISPLAY Key1 : EXP OFF EXP ON 

Key2 : CENTER 

Key3 : RR OFF 

OFFCENT 

RR ON 

Key4 : CUR OFF CUR ON 

Key2 

PROCESS Key1 : AUTOOFF A―SEA A-RAIN 

Key2 : IR OFF IR 1 IR 2 

Key3 : M-TUNE 

A-TUNE 

Key4 : WKS-OFF WKS-15S WKS-30S WKS-1M 

WKS-3M 

Key3 

GUARD Key1 : MAKE 

WKS-CNT WKS-30M WKS-15M WKS-6M 

Key2 : ALM OFF 

ALM ON 

Key3 : SENS1 SENS2 SENS3 SENS4 

SENS7 SENS6 SENS5 

Key4 : ALM IN 

ALM OUT 

153

2.1.3 Functions of the cross key 

The cross key is used to move the cross cursor, rotate the EBL, change the size of the VRM 

and select items from the menu. By pushing the cross key, the cursor moves in the direction 

pushed and the EBL may be rotated. 

The cross key is used to activate the following functions. 

Dedicated key operations 

VRM 、 EBL 、 MENU 

Soft key operations 

OFF CENT、 CUR ON 、 GUARD-MAKE 

Menu operations 

MENU-FUNCTION-ZOOM SET 

Push the cross key 

BL rotates in the counterclockwise direction with < 

and clockwise direction with . 

The VRM distance becomes larger with and 

smaller with . 

V 

12 

2 

The current cross key mode is shown at 

the lower right hand corner of the screen. 

154

Use 

Mode Name 

Letter on Screen of 

Lower Reight Corner 

Enables a EBL EBL mode E 

Enables a VRM VRM mode V 

Enables a F EBL/VRM F EBL/VRM mode F 

Enables the parallel line mode Parallel line mode P 

Enables the cursor Cursor mode C 

Enables the off center mode Off center mode O 

Enables the zoom mode Zoom mode Z 

Enables the guard mode Guard mode G 

Enables the menu mode MENU mode M 

155

2.2 Explanation of Screen Readout 

PPI bearing screen display mode 

Bearing reference 

EBL bearing display mode 

EBL number 

Motion mode 

Ship’s heading bearing 

Ship’s bearing data gathering terminal 

VRM number 

#1 EBL bearing 

#2 EBL bearing 

Target expander on 

Intereference rejection on 

Image process 

Waypoint display 

Zoom center position 

#2 EBL 

EBL1R 

1045° 

2315° 

EXP 

IR 

P 

RM H-UP T006°M 

VRM1 NM 

11.75 

1.75 

22.25 

2.25 

ALM 

I 44 

#1VRM range 

#2VRM range 

Guard zone on 

Alarm sensitivity 

Alarm mode 

Echo generated 

by a target 

Guard zone 

Fixed range ring 

#1EBL 

Bearing tick 

Zoom mode on 

AS (Automatic Sea surface 

clutter suppression) 

AR (Automatic Rain and snow 

clutter suppression) 

Range 

Range ring interval 

Tune mode indicator 

(When 'A' is displayed on 

the indicator right, auto 

tune mode is on.) 

X2 

AS 

WP 

POSN 

12 

BRG 340° N 35°15.01 

2 RNG 09.3 E139°47.05 

A 

00:54 SPD 10.2 

DISPLAY PROCESS GUARD 

Soft key item 

(1st. layer) 

E 

#1 VRM 

#2 VRM 

Brilliance level 

(This mark is displayed 

temporarily, when BRIL 

key is pushed.(Level 6)) 

Cross key mode 

(EBL mode) 

Center of PPI image 

(The center is off set because 

the zoom mode is on.) 

156

Cross key mode 

(cursor mode) 

X2 

12 

2 

A 

WP 

POSN 

BRG 340° 

RNG 09.3 

N 35°15.01 

E139°47.05 

00:54 SPD 10.2 

C 

CUR 

346° 

4.96 

0:29 

Cursor mode on 

Azimuth of the cursor position 

Distance from the ship to the cursor 

Travel time to cursor position 

Azimuth of 

the waypoint 

Ship's speed 

Requires travel time 

to the waypoint 

Distance to the 

waypoint 

Waypoint data display 

Location (L/L) data display 

(ship location display mode) 

Select location display of ship, cursor 

or waypoint from the menu 

157

2.3 Explanation of Functions within the Menu 

This radar equipment has, in addition to the capability of operating using the front panel 

keys (including the soft key), the following operating functions. In this section, the composition, 

function and method of setting the menu will be explained. 

2.3.1 Menu Composition 

With this radar equipment, it is possible to switch the screen display from the Japanese 

language, to the English language and to other languages (Chinese, French, Spanish, Italian, 

Norwegian, German and Korean). 

● Please refer to "3.2.3 Switching Language Display" for the switching among languages. 

FUNCTION 

DISPLAY 

EBL1/EBL2 

EBL2 

FIX 

PLINE1 

NO 

FLOAT 

PLINE2 

YES 

POSITION 

OFF L/L TD 

CUR L/L 

WPT L/L 

VRM2 

NO 

YES 

WAYPOINT 

OFF ON 

MENU 

EBL READOUT 

ZOOM 

TM/RM 

REL 

OFF 

RM 

TRUE,MAG 

SET 

TM 

RANGE 

TIMED TX 

TX PERIOD 

NM KY KM 

OFF ON 

10 20 30 SCAN 

HDG MODE 

H-UP N-UP C-UP 

STBY PERIOD 

3 5 10 15 MIN 

PROCESS 

OFF PR1 PR2 

SELECT W/CROSS KEY’ ( ) 


PRESS ENT TO SET 


PRESS MUNU TO RETURN 


MENU 

RADAR SET-UP 1 

FUNCTION 

NEXT 

BUZZER 

0 1 2 3 4 5 6 7 

DISPLAY 


NEXT 

NEXT 

DIMMER 

TX PILSE 

(1.5NM) 

0 1 2 3 4 5 6 7 

0.08 0.25 μs 


NEXT 

(3NM) 

0.25 0.5 μs 

(6NM) 

0.5 1.0 μs 

BEARING 

TRUE MAG 


PRESS CROSS KEY ( ) 

PRESS MENU TO RETURN 





LANGUAGE ENGLISH 日本語 

中文 

FRANCAIS 

ESPANYOL ITALIANO 

NORSK 

DEUTSCH 




158

Initial Setting Menu 

MENU 

+ 

ENTER 

Push those keys simultaneously. 

GPS 

POSITION 

ANTENNA HEIGHT 

GEODETIC 

FIX MODE 

N 35°00.00 

W 135°00.00 

15 

43 

2D 3D FIX 

INITIAL SETTING 1 

RECEIVER ADJUST 

NEXT 

BEARING 

1024 

DISPLAY TIMING 

128 

MBS LEVEL 

128 

MBS RANGE 128 

GAIN PRESET 128 

128 

COMPARATOR PRESET 

128 

STC PRESET 


UNDER 5m 

GPS PRESET 

NEXT 


NEXT 

MOTOR 

ON OFF 

TUNE PRESET 128 

TUNE FREQUENCY 50 

TUNE LEVEL IND. 50 

DOP LEVEL 

UP TO 5 UP TO 10 UP TO 20 

POSN AVARAGE 

LONG STANDARD NONE 

EXCUSION SAT. 

00 01 02 03 04 05 

SEND DATA 






GPS PRESET 

DGPS PRESET 


GPS 

DGPS 

CONDITION 

NEXT 

NEXT 

NEXT 

MODE 

FREQUENCY 

BAUD RATE 

MANUAL AUTO 

200.0kHz 

50 100 200 

SEND DATA 

SELECT W/CROSS KEY ( ) 

PRESS CROSS KEY ( ) 





GPS 

SAT NO. 

AZIMUTH 

ELV. 

SNR 

CONDITION 

SAT NO. 

AZIMUTH 

ELV. 

SNR 

SAT NO. 

AZIMUTH 

ELV. 

SNR 

VERSION: 

DOP: 

ALITUDE: 

RSSI[BEACON]: 

DATE/TIME:21 JAN 2002 

(UTC) 11:14 


SET TD NUMBER 1 2 

SIMULATOR 

OFF ON 




159

2.3.2 Functions within the menu 

When using functions marked with [*], connectivity to an external navigation 

system is required. 

FUNCTION 

Select the operating function 

of EBL1 and VRM1. 

Select use of EBL2. 

Select use of VRM2. 

Select read for the azimuth 

value of EBL. 

Display any random portion of 

the PPI image enlarged to 

twice the original image. 

* Select "relative" or "true" 

motion display. 

* Select the method of displaying 

the bearing of the 

PPI screen. 

Select the correlative processing 

of the radar echo. 

FUNCTION 

EBL1/EBL2 

FIX FLOAT 

PLINE1 PLINE2 

EBL2 

NO YES 

VRM2 

NO YES 

EBL READOUT 

REL TRUE,MAG 

ZOOM 

OFF SET 

TM/RM 

RM TM 

HDG MODE 

PROCESS 


OFF PR1 PR2 




160

DISPLAY 

* Select the information to be 

displayed on the screen 

from the positional information 

of the ship's heading 

(latitude/longitude; L/L 

or time difference; TD) or 

the location information of 

the waypoint. 

* Display the waypoint on 

the PPI screen. 

Select the units for the distance 

measured by the VRM or 

cursor. 

NM : Nautical miles 

KY : Kilo yards 

KM : Kilometers 

POSITION 

WAYPOINT 

RANGE 

TIMED TX 

TX PERIOD 

STBY PERIOD 

DISPLAY 

OFF L/L TD 

CUR L/L 

WPT L/L 

OFF ON 

NM KY KM 

OFF ON 

10 20 30 SCAN 

3 5 10 15 MIN 

For energy saving purposes, 

transmission mode and 

standby mode are automatically 

switched. 




The duration of the transmission 

mode time is set based on 

the rotation of the scanner 

unit. 

Set the duration of the standby 

time. 

161


Set the buzzer sound. 

The sound becomes louder as the 

value becomes larger. 

Set the lighting of the operation 

panel. 

The panel becomes brighter as 

the value becomes larger. 

Set the pulse width. 

Settings may be selected from 

1.5NM, 3NM or 6NM. 

・ The smaller the width, the 

greater the resolution will be. 

・ The wider the width, the 

greater the sensitivity will be. 

Select the azimuth data to be 

adopted. 


BUZZER 

0 1 2 3 4 5 6 7 

DIMMER 

0 1 2 3 4 5 6 7 

TX PILSE 

(1.5NM) 

0.08 0.25 μs 

(3NM) 

0.25 0.5 μs 

(6NM) 

0.5 1.0 μs 

BEARING 

TRUE MAG 






Set the language of the letters on 

the display. 

Selection may be from among 

the following. 

English, Japanese 

Chinese, French 

Spanish, Italian 

Norwegian, German 

Korean 

LANGUAGE ENGLISH 日本語 

中文 

FRANCAIS 

ESPANYOL ITALIANO 

NORSK 

DEUTSCH 




162


This menu appears when the MENU key and ENTER key are pushed simultaneously. 

Implement various adjustments 

on the receiver (including rough 

tuning adjustment) 

Adjust the bearing of the image 

on the PPI screen. 

Adjust the distance of the image 

on the PPI screen. 

Adjust the strength of the main 

bang suppression. 

Adjust the range of the main 

bang suppression. 

Adjust the maximum sensitivity 

when the GAIN control is 

turned fully to the right (maximum 

sensitivity). 

Normally, the maximum is set 

at 255. 


RECEIVER ADJUST 

NEXT 

BEARING 

1024 

DISPLAY TIMING 

128 

MBS LEVEL 

128 

MBS RANGE 128 

GAIN PRESET 

128 

COMPARATOR PRESET 

128 

STC PRESET 

128 


UNDER 5m 

GPS PRESET 

NEXT 


NEXT 




Adjust the criterion level when 

the radar image signal is A/D. 

Adjust the strength of the sea 

surface clutter suppression. 

Select the height to the scanner 

unit as follows: 5m or less/ 5 to 

10m/ 10m or more. 

It optimizes the characteristics 

of the sea surface clutter suppression 

by this setting. 

When connected to an external 

GPS, set the initial value of the 

GPS. 

Display the menu "INITIAL 

SETTING 2". 



SET TD NUMBER 

1 2 

SIMULATOR 

OFF ON 

Set the time differential receipt 

number. 

Display the PPI screen for 

demonstration purposes. 




163

3 Basic Operations 

3.1 Flow of Operations 

Turning the power on and starting the system 

Adjusting the turning 

Adjusting the monitoring and video 

Data acquisition and measurement 

Ending operation and stopping the system 

Basic operations are explained on the following pages 

164

Soft key operation 

The basic operations using the soft key are as follows. 

From among the 4 switches that are positioned below the screen, push the switch that 

corresponds to the required function. The items are displayed at the lower part of the 

screen and the required setting may be undertaken by pushing the switch that corresponds 

to the desired items. 

Push the MENU key to return to the lowermost tier item. 

X2 

WP 

POSN 

12 

BRG 340° N 35°15.01 

2 RNG 09.3 E139°47.05 

A 

00:54 SPD 10.2 

DISPLAY PROCESS GUARD 

E 

CUR 

346° 

4.96 

0:29 

Soft Keys 

165

3.1.1 Turning the power ON and starting the system 

1. . Turning the power ON 

In order to turn the power on, push the 

STBY/OFF key. 

When the power is turned on, a count down timer is displayed on the screen and the 

system enters the standby state after 1 minute and 30 seconds. 

Moreover, cumulative energized time and cumulative transmission time are also displayed. 

This is used as an indicator for when maintenance is required. Time displays 

may incorporate some small errors. 

2. Undertake transmission 

In order to transmit from the standby mode, push the 

X-MIT/OFF key. 

When returning from the transmission mode to the standby mode, push the 

STBY/OFF key. 

3.1.2 Tuning operation 

The tuning operation of this radar equipment may be undertaken manually or 

automatically. Switching between manual operation and automatic operation is 

undertaken using the soft key. In the case of automatic tuning, the letter "A" will be 

displayed at the right of the lower left hand tune level indicator. 

(a) Switching tuning modes 

Push the soft key 

PROCESS . 

Each time key 3 is pushed, the mode sequentially changes between A-TUNE 

and M-TUNE 

and if the manual mode is preferred, key 3 should be pushed so 

that M-TUNE 

is selected. 

(b) Turn the [TUNE] control 

In the case of manual tuning, rotate the [TUNE] control on the operation panel to 

maximize the size of the image. The tune level indicator acts as an indicator when 

undertaking manual tuning and should be adjusted so that the indicator is at the 

maximum position. 

In the case of automatic tuning, there is no need to turn the [TUNE] control. 

In the event no image appears, turn the [GAIN] control on the control panel all the 

way to the right and set [SEA] control and the [RAIN] control furthermost to the left. 

166

3.1.3 Adjusting monitoring and image 

Display the optimal image by adjusting the [TUNE] control (in the case of manual 

tuning), [GAIN] control, [SEA] control and [RAIN] control on the control panel. 

The range of monitoring distance may be switched by pushing the "▲ (up)" or "▼ 

(down)" of on 

RANGE 

key. 

The distance range currently selected will be displayed at the lower left hand corner of 

the display (please refer to "2.2 Explanation of Screen Readout"). 

3.1.4 Data acquisition and monitoring 

Please refer to "3.3 Basic Operations" and "4 How to Interpret the PPI Screen" for the 

various operations. 

3.1.5 Ending the operation and shutting down the system 

1. Interrupting the transmission 

(a) Push the 

STBY/OFF key. 

The transmission will be interrupted and the display will return to the standby mode. 

2. Shutting the power off 

(a) Push the 

X-MIT key and the 

STBY/OFF key simultaneously. 

The radar will stop operation and all functions will shut down. 

WARNING 

When performing such work as maintenance, shut the power off and disconnect 

the power connector between the rectifier and the display to cease 

supply of electricity to the system. 

Even if the power switch is off, electricity may be flowing internally in the 

various equipments and performing maintenance and repair under such 

conditions may cause accidents such as severe electric shock or equipment 

breakdown. 

167

3.2 Monitoring Standby 

3.2.1 Changing the brightness of the screen 

(a) Push the 

BRIL/HL OFF key. 

Each time this key is pushed, the brightness of the screen increases by a step. 

When the brightness is at the 8th step (maximum) and if the switch is again pushed, 

the brightness will be reduced by one step. When the power is turned on, the 

brightness level is set at "7". 

3.2.2 Changing the brightness of the control panel lighting 

(a) Select levels "0" through "7" in the line "DIMMER" - the menu "RADAR SET-UP 1". 

The higher the selected number, the brighter the lighting. 

(b) Push the 

MENU 

key. 

Menu setting has been completed. 

3.2.3 Switching among display languages 

The language display on the screen may be switched among English, Japanese and 

other languages (Chinese, French, Spanish, Italian, Norwegian, German and Korean). 

(a) Select the desired language in the line "LANGUAGE" - the menu "RADAR SET-UP 2". 

(b) Push the 

MENU 

key. 

The menu setting has been completed. 

3.2.4 Setting the buzzer volume 

(a) Select levels "0" through "7" in the line "BUZZER" - the menu "RADAR SET-UP 1". 

The higher the selected number, the louder the buzzer. 

(b) Push the 

MENU 

key. 


168

3.3 Basic Operations 

3.3.1 Transmitting 

(a) Push the 

X-MIT/OFF key. 

The system will switch from standby mode to transmission mode. 

3.3.2 Interrupting transmission 

(a) Push the 

STBY/OFF key. 

The system will switch into standby mode and the legend "Standby" will appear on the 

screen. 

3.3.3 Changing the range (scale of distance) 

(a) Push the 

RANGE key. 

Pushing the "▲(up)" key increases the scale of distance. 

Pushing the "▼(down)" key decreases the scale of distance. 

3.3.4 Erasing and displaying the fixed range ring 

(a) Push the soft key 

DISPLAY . 

(b) Push the soft key 3 and when erasing the scale, select RR OFF and when 

displaying, select 

RR ON . 

(c) Push the MENU key. 

The soft key menu will return to the initial function display. 

169

Range 

Range ring 

interval 

3.3.5 Erasing ship's heading marker 

(a) Continue to push the 

BRIL/HL OFF key for 2 seconds or more. 

The ship's heading marker shows the heading of the ship. 

While the BRIL/HL OFF key is being pushed, the ship's heading marker 

will disappear and will again be displayed when the key is released. 

Ship's heading 

marker 

170

3.3.6 Adjusting the tuning 

Please refer to "3.1.2 Tuning operation". 

3.3.7 Adjusting the sensitivity 

Attention 

• Please ensure that the sensitivity adjustment is made to an optimal level when 

undertaking monitoring. 

• If the sensitivity is too low, hazardous objects, ships and other floating objects 

may not be displayed. 

• If the sensitivity is too high, receiver noise at the PPI screen will increase and this 

may impair monitoring. 

(a) Turn the [Gain] control. 

・When the control is turned in the counterclockwise direction, the sensitivity decreases 

and when the control is turned in the clockwise direction, the sensitivity 

increases. 

・In general, optimal adjustment of sensitivity is as follows. 

The image size of the echo from the intended target is maximized. 

It does not come into contact with echoes from other targets. 

The image of the echo is 

small as the sensitivity is 

too low. 

The sensitivity has been 

adjusted to an optimal level. 

Images overlap as the sensitivity 

is too high. 

171

3.3.8 Eradicating radar interference 

Attention 

• Weak echo images from hazardous objects such as other vessels may also be 

rejected when using the interference rejection function. 

• When observing radar beacons or SART signals, make sure that the interference 

rejection function is disabled. 

Radar interference refers to the phenomenon by which microwaves transmitted by a 

third party radar is picked up directly by the ship's scanner unit and is displayed on the 

PPI screen. 


PROCESS . 

(b) Push soft key 2 to select 

IR 1 . 

(c) If radar interference cannot be rejected using 

IR 1 , push soft key 2 and 

select IR 2 . 

When not undertaking interference rejection, push soft key 2 and select 

IR OFF . 

(d) Push the 

MENU key. 


Interference rejection is enabled. 

Prior to rejection of interference 

After rejection of interference 

Example of radar interference 

172

3.3.9 In the event of rain or snow 

CAUTION 

Refrain from setting the rain and snow clutter suppression function needlessly. 

Doing so may suppress echoes from targets such as other vessels for hazardous 

objects in addition to echoes from rain and snow thus impairing detection. 

When using the rain and snow clutter suppression function, ensure that the 

suppression setting is always at an optimal level. 

When rain or snow falls, echo from the rain or snow (rain clutter) appears on the PPI 

screen making it difficult to see images of echoes from vessels or other objects. 

By using the [RAIN] control function or the "automatic rain and snow" function, rain 

clutter may be suppressed facilitating monitoring of the target. 

When the "automatic rain and snow" function is operating, it is not possible to use the 

[RAIN] control function. 

Manual rain and snow clutter suppression 

(a) Turn the [RAIN] control. 

As the control is turned to in the clockwise direction, the rain and snow clutter 

suppression function becomes stronger. 

Automatic rain and snow clutter suppression 


PROCESS . 

(b) Push the soft key 1 and select 

A-RAIN . 

Rain and snow clutter suppression is enabled depending on the condition of the image. 

(c) Push the MENU key. 


Rain clutter is being shown as an 

image 

173 

Rain clutter has been suppressed (the 

image of the echo from the target is 

also suppressed).

3.3.10 In case of high waves 

CAUTION 

On short range scales, the setting of the sea surface clutter suppression should 

not be advanced to an extent that results in complete suppression of all clutter. 

Such a setting may suppress echoes from targets such as vessels or hazardous 

objects in addition to echoes from the waves and thus impair detection. 

When using the sea surface clutter suppression function, be sure that the suppression 

level is set at the optimum. 

When sea waves become high, echoes from the high waves (sea clutter) appear on the 

PPI screen making it difficult to see image of echoes from vessels or other objects. Sea 

clutter is increasingly prominent to the extent that its source is close to the ship. 

By using the [SEA] control function or the "automatic sea surface" function, sea surface 

clutter may be suppressed facilitating monitoring of the targets. 

Manual sea surface clutter suppression 

(a) Turn the [SEA] control in the clockwise direction. 

As the control is turned in the clockwise direction, suppression of sea surface 

clutter increases. 

Automatic sea surface clutter suppression 


PROCESS . 

(b) Push the soft key 1 to select 

A-SEA . 

Sea surface clutter suppression is enabled depend on the condition of the image. 

(c) Push the 

MENU 

key. 

The soft key will return to the initial function display. 

Sea clutter being displayed as 

image due to high waves. 

174 

Sea clutter has been suppressed (the 

image of the echo from the target has 

also been suppressed).

3.3.11 Measuring the range to the target 

To measure the range to the target, the operator may take one of the following actions. 

• Use VRM (Variable Range Markers) 

• Move the center of the VRM (floating EBL) 

• Use the parallel line cursor 

• Use the cursor 

1. Using VRM 

• A VRM is a circle that is displayed on the PPI screen. 

• Since the size of the VRM may be change at will using the upper or lower portion 

of the cross key, the operator is able to measure the range of any desired target. 

• This radar equipment is capable of displaying two VRM simultaneously (#1VRM 

and #2VRM). 

• The #1VRM and #2VRM are displayed, selected and erased using the 

VRM 

key. 

• Whether or not the #2VRM is enabled is set at the menu. 

• A VRM can take on the following states: 

The VRM is not displayed. 

The VRM is displayed 

The cross key is not in VRM mode. 

The cross key is in VRM mode 

The VRM to be used (#1VRM or #2VRM) is not selected. 

The VRM to be used (#1VRM or #2VRM) is selected. 

Measuring the distance from the ship using #1VRM 

(a) Select "FIX" in the line "EBL1/VRM1" - the menu "FUNCTION". 

The #1VRM value represents the distance from the ship. 

The center of #2VRM is always fixed at the position of the ship. 

Setting whether or not use of #2VRM is enabled 

(a) Select "YES" in the line "VRM2" - the menu "FUNCTION". 

Use of #2VRM will be enabled. 

If "NO" is selected, use of #2VRM will be disabled. 

Operating the #1VRM/#2VRM 

(a) Push the 

VRM 

key. 

Each time the VRM key is pushed, the VRM that may be operated using the cross 

key changes sequentially between #1VRM and #2VRM. 

The #1VRM/#2VRM that is currently enabled is the VRM value at the upper left 

of the screen that is enclosed with dotted lines. 

175

(b) Push the left or right side of the cross key. 

This enables operating the VRM selected in (a). 

• When the lower portion of the cross key is pushed, the size of the VRM will be 

reduced. 

• When the upper portion of the cross key is pushed, the size of the VRM will be 

increased. 

Erasing the #1VRM and #2VRM 

(a) Push the 

VRM 

key. 

• When both #1VRM and #2VRM are displayed. 

Push the VRM key and enclose the value of the #1VRM or #2VRM that is to 

remain on the screen with dotted lines. 

• When either #1VRM or #2VRM is displayed. 

Enclose the displayed #1VRM or #2VRM in dotted lines. 

(b) Continue pushing the 

VRM 

key. 

The #1VRM or #2VRM selected in (a) will be erased. 

2. Moving the center of the VRM 

• Please refer to "3.3.14 Floating VRM and EBL" for the method of using the 

floating EBL. 

3. Changing the interval between the parallel line cursors 

• Please refer to "3.3.15 Using the parallel line cursor" for the method of using the 

parallel line cursor. 

4. Using the cross hair cursor 

• Please refer to "3.3.18 Simultaneously measuring the bearing, distance, and 

travel time to the target" for the method of using the cross hair cursor. 

176

3.3.12 Changing the range unit 

With this radar equipment, the range unit measured using the VRM or cross hair cursor 

may be selected from among the following. 

NM (nautical miles) 

KM (kilometers) 

KY (kilo yards) 

(a) Select among "NM", "KY", or "KM" in the line "RANGE" - the menu "DISPLAY". 

(b) Push the 

MENU 

key. 


3.3.13 Measuring the bearing of a target 

To measure the bearing of a target, the operator may select one of the following actions. 

• Use EBL (electronic cursor) 

• Move and use EBL (floating EBL) 

• Use the parallel line cursor 

• Use the cursor 

There are three modes in displaying the EBL bearing 

• Relative bearing display : R 

• True bearing display : T 

• Magnetic bearing display : M 

• For details on display of bearing, please refer to "3.3.16 Switching the EBL and 

cursor bearing display among relative, true and magnetic bearing display 

mode". 

177

1. Using EBL 

• An EBL is a straight line that is displayed on the PPI screen. 

• Since the bearing of an EBL can be changed at will using the left and right portion 

of the cross key, the operator is able to measure the bearing of any desired 

target. 

• This radar equipment is capable of displaying 2 lines of EBL simultaneously 

(#1EBL, #2EBL). 

• The #1EBL and #2EBL are displayed, selected and erased using 

the 

EBL 

key. 

• Whether or not the #2EBL is enabled is set at the menu. 

• An EBL can take on the following states: 

The EBL is not displayed. 

The EBL is displayed 

The cross key is not in EBL mode. 

The cross key is in EBL mode 

The EBL to be used (#1EBL or #2EBL) is not selected. 

The EBL to be used (#1EBL or #2EBL) is selected. 

Measuring the distance from the ship using #1EBL 


The #1EBL value represents the bearing of the target with the ship as point of 

reference. 

The point of reference of #2EBL is always fixed at the position of the ship. 

Setting whether or not use of #2EBL is enabled 

(a) Select "YES" in the line "EBL2" - the menu "FUNCTION". 

Use of #2EBL will be enabled. 

If "NO" is selected, use of #2EBL will be disabled. 

Operating the #1VRM/#2VRM 

(a) Push the 

EBL 

key. 

Each time the EBL key is pushed, the EBL that may be operated using the cross 

key changes sequentially between #1EBL and #2EBL. 

The #1EBL/#2EBL that is currently enabled is the EBL value at the upper left of 

the screen that is enclosed with dotted lines. 

(b) Push the left or right side of the cross key. 

This enables operating the EBL selected in (a). 

• When the left side of the cross key is pushed, the EBL rotates in the counterclockwise 

direction. 

178

• When the right portion of the cross key is pushed, the EBL rotates in the 

clockwise direction. 

Erasing the #1EBL and #2EBL 

(a) Push the 

EBL 

key. 

• When both #1EBL and #2EBL are displayed. 

Push the EBL switch and enclose the value of the #1EBL or #2EBL that is to 

remain on the screen with dotted liens 

• When either #1EBL or #2EBL is displayed. 

Enclose the displayed #1EBL or #2EBL in dotted lines. 

(b) Continue pushing the 

EBL 

key. 

The #1EBL or #2EBL selected in (a) will be erased. 

2. Moving the center of the EBL 

• Please refer to "3.3.14 Floating VRM and EBL" for the method of using the free 

floating EBL. 

3. Changing the interval between the parallel line cursors 

• Please refer to "3.3.15 Using the parallel line cursor" for the method of using the 

parallel line cursor. 

4. Using the cross hair cursor 

• Please refer to "3.3.18 Simultaneously measuring the bearing, distance and 

travel time to target" for the method of using the cross hair cursor. 

179

3.3.14 Floating VRM and EBL 

Use the floating EBL function to move a VRM or an EBL. 

Only #1EBL and #1VRM may be moved. 

Setting the #1EBL and #1VRM to enable moving 

(a) Select "FLOAT" in the line "EBL1/VRM1" - the menu "FUNCTION". 

The point of reference of #1EBL and center of #1VRM is now movable. 

However, the location of the point of reference of #1EBL and the center of #1VRM 

is always at the same position. 

Setting the point of reference and center er position 

(a) Push the 

EBL key or the VRM 

key. 

The cross key will become the floating EBL or floating VRM. 

The position information on the mark displayed by the marker is displayed at the 

lower right of the screen. 

The marker information is displayed only until the point of reference and center 

positions are determined. 

(b) Use the cross key and push the 

ENTER 

key. 

The set marker position will be determined as the point of reference of #1EBL and 

center of #1VRM. 

Operating the EBL and VRM 

The method of operation is the same as for normal EBL and VRM. 

• Only "setting the point of reference/ center position" is operable and if the EBL 

key had been pushed, the operation is only with #1EBL while if the VRM key 

had been pushed, the operation is only with #1VRM. 

• The point of reference and center position may be moved only for #1VRM and 

#1EBL. Prior to operation, be sure to select either #1EBL or #1VRM. 

• Please refer to "3.3.11 Measuring the range to the target" - "1. Using VRM", 

"3.3.13 Measuring the bearing of a target" - "1. Using EBL" 

Canceling the point of reference or center position 


The floating EBL will be canceled and the point of reference and center position 

will be fixed to the location of the ship. 

180

3.3.15 Using the parallel line cursor 

The parallel line cursor function is set to #1EBL and #1VRM 

(a) Select "PLINE 1" or "PLINE 2" in the line "EBL1/VRM1" - the menu "FUNCTION". 

When setting to PLINE 1, the parallel line cursor is displayed in half circumference. 

When setting to PLINE 2, the parallel line cursor is displayed in a full circumference. 

Operating the parallel line cursor 

(a) Push the 

EBL key or the VRM 

key. 

Depending on the setting at the line "EBL1/EBL2" of the menu "FUNCTION", the 

parallel line cursor will be displayed in a half circumference or full circumference. 

However, it is necessary to set #1EBL or #1VRM to operational mode using the 

cross key. 

(b) Set the bearing and interval of the parallel line cursor by operating the cross key 

in the up-down and left-right directions. 

• When the upper portion of the cross key is pushed, the interval increases. 

• When the lower portion of the cross key is pushed, the interval decreases. 

• When the left side of the cross key is pushed, the parallel cursor turns in the 

counterclockwise direction. 

• When the right side of the cross key is pushed, the parallel cursor turns in the 

clockwise direction. 

Canceling the parallel line cursor 


The parallel line cursor display is canceled and use of normal #1EBL and #1VRM 

will be enabled. 

3.3.16 Switching the EBL and cursor bearing display among relative, true and 

magnetic bearing display mode 

There are three methods of displaying the bearing using EBL and the cursor. 

• Relative bearing display: 

This is the bearing of an EBL or cursor displayed with the bearing of the ship's 

bow (ship's heading marker) taken as 0 degrees. 

• True bearing display (Note) : 

This is the bearing of an EBL or cursor displayed with the bearing of true north 

(north pole) taken as 0 degrees. 

181

• Magnetic bearing display: 

This is the bearing of an EBL or cursor displayed with the north indicated by a 

magnetic compass taken as 0 degrees. 

(Note): The term "true bearing" and the terms "gyro bearing" or "gyrocompass 

bearing" used hereafter shall have the same meaning. 

• In order to display the true bearing or magnetic bearing, it is necessary to input the 

bearing information to the display. 

Please refer to "3.6.1 Obtaining information on bearing" with respect to bearing information. 

R: EBL relative bearing display 

Relative azimuth angle of #1EBL 

Relative azimuth angle of #2EBL 

T: EBL true bearing display 

True azimuth angle of #1EBL 

True azimuth angle of #2EBL 

M: EBL magnetic bearing display 

Magnetic azimuth angle of #1EBL 

Magnetic azimuth angle of #2EBL 

182

Selection of bearing criteria (magnetic bearing, gyrocompass bearing) 

Select the bearing criteria as follows. 

When the connected device a magnetic compass: MAG 

When the connected device is a gyrocompass: TRUE 

When GPS or LORAN is connected and the display mode does not become the true 

bearing display mode even when (a) has been undertaken, switch to the other bearing 

criterion. 

(a) Select "MAG" or "TRUE" in the line "BEARING" - the menu "RADAR SET-UP 1". 

(b) Push the 

MENU 

key. 


Selection of the bearing criteria 

(a) Select "REL" or "TRUE, MAG" in the line "EBL READOUT" - the menu "FUNC- 

TION". 

• When "REL" is selected, the bearing of the EBL when the ship's bow (ship's 

heading marker) bears to 0 degrees is displayed. 

• When "TRUE, MAG" is selected, the bearing of the EBL when the device selected 

under "BEARING" above detects "north" is assumed to be 0 degrees is 

displayed. 

3.3.17 Changing the bearing display method of the PPI screen 

The methods of display of the radar PPI screen consist of the following. 

• Relative bearing display (head-up display) 

The ship's bow is displayed directly at the top of the PPI screen (bearing scale 0 degrees). 

When the bearing of the ship's bow changes, the bearing of the echo image on the 

PPI screen also changes. 

When bearing information cannot be obtained from such navigation devices as 

gyrocompass, display is by this relative bearing method. 

The ship rotates 

in the starboard direction 

183 

The PPI image rotates counterclockwise

• True bearing display (north-up display) 

"North" is displayed as direct north of the PPI screen. 

Even when the bearing of the ship's bow changes, the bearing of the PPI image 

does not change. 

(Gyrocompass or other device that provides bearing information is required.) 



The ship's heading marker 

rotates clockwise. 

• Course-up display 

The bearing of the ship's bow is always directly at the top of the PPI screen when 

the BRIL/HL OFF 

key is continuously pushed (course setting). 

Even when the bearing of the ship's bow changes, the bearing of the echo image 

on the PPI screen does not change and the ship's heading marker rotates to the 

extent of the change in the bearing of the ship's bow. 

When the heading changes significantly, the course should be reset by pushing 

the BRIL/HL OFF key continuously. 

(Gyrocompass or other device that provides bearing information is required.) 



The ship's heading marker 

rotates clockwise. 

BRIL 

HL OFF 

184

• In order to change the method of bearing display on the PPI screen, it is necessary 

to input the bearing information from a navigation device. 

Please refer to "3.6.1 Obtaining information on bearing" with respect to bearing 

display. 

Course setting in course-up up mode 

(a) Continue to hold down the 

BRIL/HL OFF key. 

The course will be set at the top of the PPI screen. 

3.3.18 Simultaneously measuring the bearing, distance and travel time to the target 

The cursor function is used for this measurement. 

The cursor that is used here is indicated by a "+" mark on the PPI screen. 

By using this function, in addition to the distance to the cursor, the bearing and travel 

time to the cursor position may be obtained. 

• In order to obtain the travel time, it is necessary to input the ship's speed information 

from a navigation device. 

Please refer to "3.6.2 Obtaining information on speed". 

185

Displaying the cursor 


DISPLAY . 


CUR ON . 

Information will be shown as follows at the lower right of the screen. 

The cross key is in cursor mode. 

The cursor function is operating. 

Azimuth angle from the bearing of the 

ship's bow to the cursor. 

Distance from the ship to the cursor. 

Travel time when traveling from the 

ship's position to the cursor position. 

• When information on speed is input, the maximum travel time displayed is 

"9:59". 

• The cursor will appear on the PPI screen and the cross key will enter cursor 

mode. 

Moving the cursor 

(a) Operating the cross key. 

When cursor movement is abandoned, the bearing and distance to that point and 

the required travel time to that point are displayed. 

Erasing the cursor 


DISPLAY . 


CUR OFF . 

The cursor, bearing, distance and required travel time will be erased. 

186

3.3.19 L/L display of the cursor 

• In order to use this function, it is necessary to input the ship's position information 

from a navigation device. 

Please refer to "3.6.3 Obtaining information on position " with respect to information 

on the ship's position. 

• Select "TRUE" in the line "BEARING" - the menu "RADAR SET-UP 1". 

• If the setting is "MAG" and information for converting magnetic bearing values into 

gyro bearing values is input from a navigation device, L/L display will be undertaken 

but when such conversion is not possible, such display will not be made as 

errors will be generated in the L/L value. 

3.3.20 Magnifying the echo images on the PPI screen 

The following methods may be used to magnify the echo images that are shown on the 

PPI screen. 

• Use the image expansion function 

• Set the transmission pulse width wider 

• Use the zoom function 

1. Using the image expansion function 

The expansion function enlarges the echo images on the PPI screen in the angle direction 

and distance direction. 

Attention 

• When the image expansion function is used, two targets that are in close proximity 

in the range direction (depth) and angle direction may be shown as one image on 

the PPI screen. 


DISPLAY . 

(b) Push soft key 1 and select 

EXP ON. . 

187

Before magnified 

After magnified 

2. Changing the transmission pulse width 

With respect to ranges of 1.5 NM, 3 NM and 6 NM, the transmission pulse width may 

be changed. 

If a wider pulse width is selected, the echo images on the PPI screen will be extended in 

the range direction. Conversely, when a narrower pulse width is selected, the image is 

compressed (made shorter) in the range direction. 

The difference of this function from the image expansion function is that when the 

pulse width becomes wider, echoes that had not been visible are sometimes visible as 

images. 

Attention 

• When switching to a wide pulse width, two targets that are in proximity in the range 

direction (depth) may be shown as one echo on the PPI screen. 

(a) Select "1.5NM", "3NM", or "6NM" in the line "TX PULSE" - the menu 

"RADAR SET-UP 1". 

188

Before magnified (narrow pulse width) 

After magnified (wider pulse width) 

3. Using the zoom function 

The zoom function allows any given area on the PPI screen to be enlarged by a factor of two. 

The area to be enlarged is designated using the marker. 

•This function is disabled when the 0.125NM range is in use or TM is in use or the 

floating EBL function is active. 

Setting the zoom area 

(a) Select "SET" in the line "ZOOM" - the menu "FUNCTION". 

The marker "+" will appear on the PPI screen. 

(b) Position the marker in the desired location using the cross key. 

•The marker can be moved within up to 66% of the monitoring range. 

(c) Push the 

ENTER 

key. 

The area with the marker at the center will be enlarged by a factor of two. 

189

Location designated by the marker 

Canceling the zoom 

(a) Select "OFF" in the line "ZOOM" - the menu "FUNCTION". 

The zoom function will be canceled. 

3.3.21 Reducing unnecessary noise and emphasizing the target 

Attention 

• Do not use this function when observing radar beacon, SART signal or a target 

that moves at high speed across the radar screen. 

• This function is optimized in TM mode. 

• When using this function in RM mode, please use N-UP or C-UP. If used with 

H-UP, the image may blur. 

Set the image processing 

(a) Select "PR1" or "PR2" in the line "PROCESS" - the menu "FUNCTION". 

• PR1: This is used when there is a target that is moving at low speed. 

Images of relatively unstable targets are emphasized and displayed in a 

stable manner. 

This function has the effect of suppressing irregular signals such as sea 

surface clutter. 

However, images of targets that are moving at high speed will become weak. 

As a rule of thumb, the function should be used at ranges of 1.5NM or less. 

190

PR2: This function is used in stabilizing unstable images using PR1. 

This function is effective when sea surface clutter is abundant. 

As a rule of thumb, the function should be used at ranges of 3NM or more. 

Canceling image processing 

(a) Select "OFF" in the line "PROCESS" - the menu "FUNCTION". 

The image processing function has been canceled. 

3.3.22 Moving the center of the PPI screen 

By moving the center of the PPI screen (relocating the center), it is possible to extend 

the range in any given direction. 

•This function is disabled when the zoom function is enabled or the maximum Range 

is in use. 

Setting the position to which the center is relocated. 


DISPLAY . 

(b) Push the soft key 2 and select first 

OFF CENT and then CENTER . 

The marker will be displayed on PPI screen. 

(c) Use the cross key to position the marker at the center of the desired PPI screen. 

•The marker may be moved up to within 66% of the monitoring range. 

(d) Push the 

ENTER key. 

The center of the PPI screen will move to the designated location. 

191

Canceling center relocation 


DISPLAY . 

(b) Push the soft key 2 and select first 

CENTER and then OFF 

CENT . 

Center relocation has been canceled. 

3.3.23 Controlling power consumption of the radar 

In order to control power consumption, the timed transmission function is used. 

By using the timed transmission function, the system repeatedly alternates between 

transmission mode and standby mode. 

Setting the transmission time 

(a) Select "10", "20", or "30" in the line "TX PERIOD" - the menu "DISPLAY". 

The transmission time is designated by the rotation of the scanner unit. 

Setting the standby time 

(b) Select "3", "5", "10", or "15" in the line "STBY PERIOD" - the menu "DISPLAY". 

The standby time is designated as 3 minutes, 5 minutes, 10 minutes or 15 

minutes. 

Commencing timed transmission 

(c) Select "ON" in the line "TIMED TX" - the menu "DISPLAY". 

When this is undertaken, timed transmission begins. 

192

(d) Push the 

MENU 

key. 


1. After transmitting to the extent of the number of rotations of the scanner unit 

designated, the system enters the standby mode for the period designated. 

During standby mode, the echo from the radar disappears from the screen and 

a timer that shows the remaining time to the next transmission is shown on 

the display. 

2. After completion of the standby period, the system again transmits to the extent 

of the designated number of rotations of the scanner unit. 

3. This process is repeated. 

CAUTION 

While timed transmission is in progress, under no circumstances should the 

scanner unit be approached. 

While the scanner unit is stopped during the standby period, after completion 

of such standby period, the scanner unit will resume rotation and may collide 

with the body and cause injury. 

Canceling timed transmission 

(e) Select "OFF" in the line "TIMED TX" - the menu "DISPLAY". 

The timed transmission has been canceled. 

(f) Push the 

MENU 

key. 


Canceling timed transmission while in standby mode 

(g) Push the 

STBY 

key. 

The timed transmission mode will be canceled and the system will return to 

normal standby mode. 

193

3.3.24 Locking a fixed target on the radar PPI screen while the ship is navigating 

Normally, the PPI image moves as the ship moves. 

This method of display is called: 

Relative Motion : RM 

In contrast to this, the display mode in which the echo images from fixed targets such 

as land do not move and the location of the ship (center of the PPI) moves according to the 

course and speed of the ship is called: 

True Motion : TM 

• In order to undertake TM display, it is necessary to input bearing information and the 

ship's speed information from a navigation device. 

Please refer to "3.6.1 Obtaining information on bearing" and "3.6.2 Obtaining information 

on speed" with respect to information on bearing and on speed. 

Commencing True Motion display 

(a) Select "TM" in the line "TM/RM" - the menu "FUNCTION". 

The motion display on the PPI screen will change to "TM". 

• The bearing display with TM is enabled is only N-UP. 

True Motion Display mode: TM 

FUNCTION 

EBL1/EBL2 

EBL2 

FIX 

PLINE1 

NO 

FLOAT 

PLINE2 

YES 

VRM2 

EBL READOUT 

ZOOM 

TM/RM 

HDG MODE 

PROCESS 

NO YES 

REL TRUE,MAG 

OFF SET 

RM TM 


OFF PR1 PR2 

SELECT W/CROSS KEY' ( ) 



194

Canceling true motion display 

(a) Select "RM" in the line "TM/RM" - the menu "FUNCTION". 

The TM is canceled and the mode is now N-UP of RM. 

Relative Motion Display mode: RM 

FUNCTION 

EBL1/EBL2 

EBL2 

FIX 

PLINE1 

NO 

FLOAT 

PLINE2 

YES 

VRM2 

EBL READOUT 

ZOOM 

TM/RM 

HDG MODE 

PROCESS 

NO YES 

REL TRUE,MAG 

OFF SET 

RM TM 


OFF PR1 PR2 

SELECT W/CROSS KEY' ( ) 



195

• The following is an example of switching from relative motion display (RM) to 

true motion display (TM) 

Select "TM" 

Relative motion display 

The center of the PPI 

moves to a location within 

66% of the radius. 

The center of the PPI 

moves together with the 

movement of the ship. 

When the center of the PPI moves to a location 

within 66% of the radius, the center 

of the PPI automatically resumes movement 

to a location 66% of the radius in the 

diagonal direction. 

196

3.3.25 Monitoring the motion of other ships (Targets) 

One of the following functions is used to monitor the movement of other ships (targets) 

• Wakes (set using the soft key) 

• Lookout alarm (set using the soft key) 

1. Radar display of wake 

It is possible to confirm the movement of other ships through the length and direction 

of the wake and this can be utilized to avoid collisions. 

The length of a wake may automatically be selected among 15 seconds, 30 seconds, 1 

minute, 3 minutes, 6 minutes, 15 minutes, 30 minutes and continuous. 

Commencing radar display of a wake 


PROCESS . 

(b) Push the soft key 4 and set the wake time to other than 

Radar display of the wake will begin. 

WKS OFF . 

Ending radar display of a wake 


PROCESS . 

(b) Push the soft key 4 and set the wake time to 

Display of the wake will be discontinued. 

WKS OFF . 

2. Using the lookout alarm 

The guard zone may be defined using the lookout alarm. 

The guard zone refers to an "area" defined on the PPI screen. 

When a target enters this "area" or exits the "area" an alarm is sounded. 

The alarm mode that is activated when a target enters a guard zone is called the IN 

mode. 

The alarm mode that is activated when a target exits a guard zone is called the OUT 

mode. 

Setting the guard zone 


GUARD . 

The marker "+" appears on the PPI screen and a dotted distance help line and 

dotted azimuth help line that indicates the distance and azimuth of the marker will 

be displayed. 

(b) Push the soft key 1 

MAKE . 

197

(c) Move the marker using the cross key. 

Move the marker to the initial point of reference of the zone to be designated. 

(d) Push the 

ENTER 

key. 

The initial point of reference of the guard zone has been designated. 

The dotted distance help line and dotted azimuth help line have been fixed. 

(e) Move the marker using the cross key. 

Move the marker to the distance range of the guard zone to be designated. 

A new dotted distance help line will be displayed. 

(f) Push the 

ENTER 

key. 

The distance of the guard zone has been set. 

A ring around the distance range will be displayed as a continuous line. 

(g) Move the marker using the cross key. 

Move the marker to change the shape of the guard zone to any desired shape. 

The form will change in the manner of a fan opening (or closing). 

(h) Push the 

ENTER 

key. 

The extremity of the guard zone has been designated and the process has been 

completed. 

Guard zone in the process 

of being designated. 

198

Changing the alarm mode 


GUARD . 

(b) Push the soft key 4 to switch the wake time between 

and ALM OUT . 

The selected alarm mode is activated. 

ALM IN 

Eradicating the guard zone 


GUARD . 

(b) Push the soft key 2 to designate 

ALM OFF . 

The guard zone that had been produced will disappear from the PPI screen and 

the lookout alarm function will be disabled. 

Calling a guard zone 


GUARD . 

(b) Push the soft key 2 to designate 

ALM ON . 

The guard zone previously produced will be displayed on the PPI screen and the 

lookout alarm function will be enabled. 

Changing the sensitivity ivity of the alarm 


GUARD . 

(b) Push the soft key 3 repeatedly to select the alarm sensitivity. 

Alarm sensitivity "1" through "7" indicates the level of the image (strength of the 

echo) at which the alarm is sounded. 

SENS 1 most readily causes the alarm to sound while SENS 7 is 

least sensitive. 

• The alarm may sound as a result of noise. 

199

3.4 Other Convenient Functions 

3.4.1 Displaying the ship's speed on the display unit 

When speed information is input to the display unit, the ship's speed is automatically 

displayed. 

Ship's speed 

• In order to use this function, it is necessary to input ship’s speed information from a 

navigation device. 

Please refer to "3.6.2 Obtaining information on speed". 

3.4.2 Displaying the ship's heading on the display unit 

When ship’s heading information is input to the display unit, the ship's heading is 

automatically displayed. 

• In order to use this function, it is necessary to input ship’s bearing information from a 

navigation device. 

Please refer to "3.6.1 Obtaining information on bearing". 

This radar equipment is capable of inputting bearing information from the following 

two input connectors at the back of the display unit. 

• CMPS+ and CMPS- terminals of the EXT1(J3) connector 

• NAVRX and NAVCOM terminals of the GPS(J4) connector. 

Input terminal display 

M : Bearing information input from CMPS+ and CMPS- terminals of 

the EXT1(J3) connector 

L : Bearing information input from NAVRX and NAVCOM terminals of 

the GPS(J4) connector 

200

The order of priority in utilizing bearing information is as follows. 

M 

L 

CMPS+, CMPS- terminals > NAVRX, NAVCOM terminals 

(priority: high) 

(priority: low) 

3.4.3 Displaying position information (latitude/longitude, LORAN C time difference) of 

the ship and waypoint information (latitude/longitude) 

Display of position information 

(a) Select among "L/L", "TD", "CUR L/L", or "WPT L/L" in the line "POSITION" 

- the menu "DISPLAY". 

When displaying latitude/longitude 

: "L/L" 

When displaying LORAN C time difference : "TD" 

When displaying L/L of the cursor 

: "CUR L/L" 

When displaying the latitude and longitude of the waypoint 

: "WPT L/L" 

Erasing location information 

(b) Select "NO" in the line "POSITION" - the menu "DISPLAY". 

The location information is erased. 

• When "L/L" is selected, it is necessary to input the ship's position (latitude and longitude) 

information from a navigation device. 

• When "TD" is selected, it is necessary to input the ship's position (LORAN C time 

difference) information is a navigation device. 

• When "CUR L/L" is selected, it is necessary to input the ship's position (latitude and 

longitude) information from a navigation device. 

• When WPT "L/L" is selected, it is necessary to input the waypoint’s position (latitude 

and longitude) information from a navigation device. 

Please refer to "3.6.3 Obtaining information on position" for details. 

201

3.4.4 Displaying the waypoint 

• In order to use this function, it is necessary to input of the following information to 

the display unit: 

Information on the bearing of the waypoint 

Information on the distance to the waypoint 

Information on the ship's speed. 

Please refer to: 

"3.6.1 Obtaining information on bearing" 

"3.6.2 Obtaining information on speed" 

"3.6.4 Obtaining information on the distance to the waypoint" 

Display of the waypoint 

(a) Select "ON" in the line "WAYPOINT" - the menu "DISPLAY". 

• The bearing, distance and required travel time (when ship speed information 

has been input) will be displayed. 

• The route from the ship to the waypoint will be displayed with the following 

marker. 

Circle : Position of the waypoint 

Refer to "2.2 Explanation of Screen Readout" 

Erasing the waypoint 

(a) Select "OFF" in the line "WAYPOINT" - the menu "DISPLAY". 

The waypoint mark, the bearing, distance and required travel time to the 

waypoint will disappear. 

202

3.5 Miscellaneous Considerations 

3.5.1 Replacing the battery (BT1) 

In order to maintain the information that has been set, the battery (BT1) needs to be 

replaced at regular intervals. 

(a) Replacing the battery (BT1) [Type: CR2032-FT6-1, SANYO Electric Co, Ltd.] 

• Please call the dealer servicing your locality for a replacement battery. 

(b) Reinitializing 

• The lithium battery maintains the content of the setting of the menu and soft 

key even when the power is shut off allowing use under the conditions of the 

last use. 

• If this battery runs down, all conditions including the menu will automatically 

be reset. 

For this reason, initializing is required after replacement of the battery. 

Attention 

• When the battery wears down, distance and bearing may become inaccurate. 

In such cases, the battery should immediately be replaced and initialization undertaken. 

• In the event immediate replacement of the battery is not feasible, initialization 

should be undertaken each time the power is turned on as an emergency 

measure. However, each time the power is shut off, the content that has 

been set is reset. 

• Please refer to "9.8 Initial Setting" with respect to details on initialization. 

203

3.5.2 In cases of abnormality during operations 

In the event such phenomena as the screen becoming disturbed or the machine not 

accepting switch input occurs during use of the radar, initialize using the procedures 

outlined below. 

Attention 

• When initialization is undertaken, all setting excluding the menu “INITIAL SET- 

TING 1” and “INITIAL SETTING 2” will be reset and the ex-factory shipment conditions. 

key simulta- 

(a) Push the 

STBY/OFF key and X-MIT/OFF 

neously. 

Power is turned off. 

(b) Push the 

MENU key, ENTER key and STBY/OFF 

simultaneously. 

Power will be turned on as in normal operation for turning on power. 

key 

204

3.6 External Navigation Devices 

• Please refer to "9.3.4 Display unit rear panel" on connections. 

This radar equipment has the following busses at the rear of the display unit. 

・NMEA 

CMPS+ and CMPS- terminals of the EXT1(J3) connector 

NAVRX and NAVCOM terminals of the GPS(J4) connector 

An external navigation device with either of these busses may be connected for input 

and output of information. 

3.6.1 Obtaining information on bearing 

In order to obtain information on the bearing of the ship, one of the following needs to 

be connected to the display unit. 

• Magnet compass 

• GPS gyro 

Bearing information is input from either the CMPS or NAVRX terminals. 

3.6.2 Obtaining information on speed 

In order to obtain information on the speed of the ship, one of the following devices 

need to be connected to the display unit. 

• GPS 

• LORAN C 

Speed information is input from either the CMPS or NAVRX terminals. 

3.6.3 Obtaining information on position 

In order to obtain information on the ship's position in terms of latitude and longitude, 

one of the following devices need to be connected to the display unit. 

• GPS 

• LORAN C 

In order to obtain the ship's position information using LORAN C time difference, the 

following needs to be connected to the display unit. 

• LORAN C 

205

In order to obtain information on the L/L of the waypoint, one of the following devices 

need to be connected to the display and the waypoint set in such device. 

• GPS 

• LORAN C 

Information on position is input from either the CMPS or NAVRX terminals. 

3.6.4 Obtaining information on distance to the waypoint 

In order to obtain information on distance to the waypoint, one of the following devices 

need to be connected to the display unit, and it is necessary that the waypoint set in the 

navigation device is displayed on screen. 

• GPS 

• LORAN C 

Information on distance is input from either the CMPS or NAVRX terminals. 

206

4 How to Interpret the PPI Screen 

4.1 Height of and the Distance to the Target 

The maximum distance to a target that can be observed with a radar depends not only on 

the power of the radar's transmitter, beam width of the scanner unit, and the receiver's 

sensitivity but also on height of a target, distance to a target and height of scanner unit line 

etc. This is because the radio wave emitted by a radar runs straight, undergoing no 

influence by the curvature of the earth surface. 

a1=2.23√h1 

a2=2.23√h2 

a1 + a2=2.23 (√h1 + √h2 ) 

a1, a2:Unit [Nautical miles] 

h1, h2:Unit [Meters] 

[Distance and Target] 

For example, when the scanner unit lies 3 meters above the sea level, the radar can 

detect and display an island with a height of 10 meters at a distance 10 NM away from 

the scanner unit position but cannot detect and display an island with a height of 5 

meters at the same distance. This is theoretically true but does not always hold, 

depending on weather conditions. 

For a target located 10 NM away to be displayed on a radar, it theoretically needs to be 

7.6 meters or higher. Any targets lower than 7.6 meters cannot be displayed on a radar. 

• The target may be unable to be observed when the height of a scanner unit or an target is low. 

Island not displayed on the screen 

10 NM 

10 NM 

h1(meters) 

Scanner unit height 

a1+a2(NM) 

Distance 

207 

h2(meters) 

Target height

4.2 Returns from a Target 

The intensity of returns from a target is related not only to the size of the target but 

also to the materials and shape of the components making up the target. Accordingly, 

larger objects do not necessarily develop strong returns. 

On coastlines, in particular, the intensity of returns is dependent on their 

physiographic features. For a coastline with a fairly gradual ascent, only inland 

mountains areas may be displayed as echoes. This fact needs to be kept in mind when 

measuring the distance to a coastline. 

• Since the echo which returns from a coastline with a fairly gradual ascent is weak, 

observation of such land may not be able to be performed. 

4.3 Propagation Path of Radio Waves 

• Radio waves may be shielded if there is a large intercepting obstacle (e.g., 

mountains, rain, snow, etc.) in their propagation path and any targets behind the 

obstacle cannot be observed. 

An island that is not displayed because of heavy 

rain in between the own ship and the island 

A ship that is not displayed because of an island 

in between the own ship and the target ship 

208

4.3.1 Sea returns 

On a wavy sea surface, an echo appears on the PPI screen as a bright defused image at the 

center of the screen. This echo is developed by returns from the sea surface. The features of 

the echo depend on the size and range of the wave, and the wind direction. 

4.3.2 False echoes 

There are cases in which nonexistent targets appear as echoes or in which existing targets 

do not appear as echoes on the PPI screen. These echoes are called false echoes. 

False echoes are produced by the factors explained below. 

• Please observe carefully in consideration of there being always false echoes. 

(a) Ghost 

Depending on the location where the scanner unit is installed, radio waves are emitted from nearby 

chimney stacks or masts, developing ghosts. Consequently, targets that are located in those direction 

may not appear as echoes on the PPI screen. 

The presence of these ghosts can be identified by observing sea returns and checking the returns for 

dim areas or voids. 

If a ghost is detected, remember the direction in which it appears and observe the target carefully. 

(b) Side echo 

There are cases in which an arc-shaped broken line appears over 

the same range as the echo from the target. This image is caused by 

the side lobes of the beam emitted from the scanner unit. This type 

of false echoes can easily be identified if the target stands alone. 

(c) Indirect echo 

The direction of the radio wave 

from the radar may be changed by a 

reflection (secondary reflection) at a 

chimney stack or mast of a ship, 

developing a false echo in a direction 

in which there should be no target. 

The indirect echo developed by the 

secondary reflection appears in the 

direction of the chimney stack or 

mast that reflected the radio wave. 

209

(d) Multiple echo 

Multiple echoes are developed by multiple reflections caused by a building or large vessels 

that has large vertical surfaces. These echoes are spaced at an equal interval, with the one 

that is closest to the own ship being the true echo. 

(e) Radar interference 

If there is a radar that uses the same frequency as that of the own ship near the own ship, 

interferences caused by that radar appear on the PPI screen. These interferences appear as 

clusters of spots of varying patterns. Since they do not occur at the same location with time, 

they can easily be distinguished from true echoes. 

Radar interferences can be reduced or eliminated by choosing "ON" from 

"FUNCTION"-"IR". 

【Examples of radar interferences】 

210

4.4 Display of Radar Transponder 

SART (Search and Rescue Radar Transponder) is life preserving device approved by 

GMDSS which is used for locating survivors in the event of a disaster or distress. SART 

operates in the 9GHz frequency band. When it receives a radar signal (interrogating 

radio wave) of 9GHz transmitted by a rescue ship or aircraft radar, SART transmits a 

series of respouse signals to the searchers to indicate the distress position. 

In order to see the SART or radar beacon mark on the radar screen. 

1 RANGE SCALE 

: Select 6 or 12 nm 

2 SEA CLUTTER control : Set to minimum 

3 AUTO SEA 

: OFF 

4 TUNE control 

: DETUNED to reduce the clutter 

5 IR 

: Set IR OFF 

6 PROCESS 

: Set PROCESS OFF 

Attention 

【Example】 

• When above settings 1to 6 are made to display SART signals, objects around 

the own ship will not appear on the radar screen, so perform thorough visual 

monitoring of the sea area around the own ship to avoid any collision or stranding. 

Further, when more than one radar systems are mounted, while using a 9GHz 

band radar for searching SART signals, be sure to use another radar as an 

ordinary radar to perform monitoring of objects around the own ship to avoid any 

collision, check of the position of the own ship to avoid any stranding, and so on. 

Need to return the set for normal operation on completion. 

211

5 Maintenance and Inspection 

5.1 General Maintenance 

WARNING 

The customer should refrain from inspecting or repairing the internal parts of this 

equipment. 

Inspection or repair other than by specialized service personnel may result in 

fire or severe electric shock. 

Please contact the sales department of Japan Radio Co., Ltd. or your local 

branch, outlet or sales office with respect to maintenance and repair. 

When performing maintenance in increment weather, please be sure to shut 

the main power off. Maintenance work performed without shutting the main 

power off may result in severe electric shock. 

CAUTION 

When cleaning the surface, please refrain from using organic solvents such as 

thinner or benzene. 

Use of such organic solvents may damage the surface coating. 

When cleaning the surface, remove dust and grime and wipe with a clean dry 

cloth. 

The following maintenance steps are required to ensure that the radar always operates in 

the optimal condition. Since breakdowns will be reduced through maintenance, periodic 

maintenance is recommended. 

General maintenance steps common to all equipment are as follows. 

Cleaning 

Remove dust, grime and sea water that has adhered to the unit. Use dry cloth to clean 

the unit. In particular, use a brush to clean the ventilating opening to ensure smooth flow 

of air. 

212

5.2 Scanner Unit 

WARNING 

When performing maintenance or inspection of the scanner unit, be sure to shut 

off the main power source. Sudden movement of the scanner may cause 

collision and injury to the human body. 

Be sure to shut off the main power source when approaching the scanner unit for 

the purposes of maintenance or inspection. Exposure to electric waves at 

proximate distances may negatively affect the human body. 

(1) Radiation unit 

If the front of the radiation unit is soiled with soot, salt, paint specks, bird excrement or 

other alien matter, electric waves may become attenuated and reflection may occur thus 

causing degradation in the performance of the radar. 

The radiation unit should be inspected and always kept clean by wiping with cloth 

soaked in alcohol or water in the event of soiling. 

Solvents such as gasoline, benzene, trichlene or ketone should never be used for this 

purpose. 

(2) Pedestal 

The pedestal and attachment bolts of the scanner unit should be inspected periodically 

for erosion and maintained to ensure safety. Painting is the best measure for preventing 

erosion and it is recommended that this be undertaken once in half a year. 

5.3 Display Unit 

Cleaning the cathode-ray tube 

When dust adheres to the cathode-ray tube, transparency degrades and the images 

become dark. 

Cleaning is performed using cloth soaked in water (flannel or cotton). Wiping 

vigorously with dry cloth or the use of gasoline or thinner should be avoided. 

CAUTION 

Vigorous wiping with dry cloth or the use of gasoline or thinner should be 

avoided in cleaning the cathode-ray tube. 

Such action may cause scratches and deterioration. 

213

5.4 Special Parts 


Model 

Number 

Name Type Manufacturer Location of use JRC Code 

V201 Magnetron MSF1421B New JRC Scanner unit 5VMAA00049 

A101 Circulator H-6AJRD00001 Toshiba Scanner unit 6AJRD00001 

A102 Diode limiter NJS6930 New JRC Scanner unit 5EZAA00024 

E301 Front end NJT1028 New JRC Scanner unit 5EZAA00039 


Model 

Number 

Name Type Manufacturer Location of use JRC Code 

V201 Magnetron MSF1422B New JRC Scanner unit 5VMAA00051 

A101 Circulator H-6AJRD00001 Toshiba Scanner unit 6AJRD00001 

A102 Diode limiter NJS6930 New JRC Scanner unit 5EZAA00024 

E301 Front end NJT1969 New JRC Scanner unit 5EZAA00037 

5.5 Circuit Blocks for Repair 

NKE-249 

Name Unit/ type of circuit Remarks 

Modulator circuit 

Receiver 

CME-307 

NRG-140 

NKE-250 

Name Unit/ type of circuit Remarks 

Modulator circuit CME-308 

Receiver 

NRG-141 

Motor unit CBP-153 With rotating pulse generation circuit 

Motor brush BRXP05247 Containing 2 

214

NCD-4170 

Name Type Remarks 

Main control circuit 

Power supply circuit 

Main panel circuit 

CMC-1156 

CBD-1596 

CCK-873 

Soft key panel circuit 

CCK—872 

Interior of the monitor unit CKJ-159 CRT + deflecting coil 

CRT monitor control unit CCN-366 With socket circuit 

215

5.6 Actions to Deal with Abnormalities and Breakdown 

In the case of semiconductor circuits, except in cases of problems in the design or inspection of 

such circuits or causes that are external or caused by humans, breakdown or deterioration of the 

circuit does not often occur. In general, the causes of breakdown that are relatively frequently 

found are wire cut in the high resistance device due to high humidity, defect in the variable 

resistance and defective contact of switches and relays. 

Moreover, in many cases the cause for breakdown is not a defect in parts but rather poor 

adjustment (particularly inadequate tuning adjustment) or poor maintenance (particularly defect in 

cable contact) and inspecting or readjusting these aspects is often effective in the case of 

perceived abnormality or breakdown. The following table should be taken into consideration in 

the case of abnormalities or breakdown. 

There is always a cause for blown fuse and after replacing the fuse, it is necessary to 

investigate the related circuits even when no abnormality remains. However, consideration 

should be given to the fact that there is significant variance in the characteristics of fuse. Please 

refer to the list on the fuses used given in Section 9.4. 

No. Condition of the Breakdown Conceivable Cause 

1 Nothing appears on the 

CRT. 

2 The scanner unit does not 

rotate. 

3 The scanner unit rotates but 

no radar image appears 

(characters and markers 

are, however, displayed). 

4 The operation switches do 

not work. 

a. Breakdown in the power supply unit (CBD-1596) 

b. Fuse F1 has blown 

c. Breakdown of the monitor 

d. Breakdown of the main control circuit (CMC-1156) 

e. The electric power of the ship is inadequate. 

a. Fuse F2 has blown 

b. Breakdown in the motor unit (JMA-2343: CML-645 

H-7BDRD0023 inside the scanner unit, JMA-2344: 

CBP-153) 

c. Breakdown of the safety switch of the scanner unit 

(JMA-2344 only) 

a. Breakdown of the receiver (JMA-2343: CAE-457, 

JMA2344: CAE-457-1) 

b. Breakdown of the main control circuit (CMC-1156). 

What is the condition of the transmission trigger (TI)? 

c. Breakdown of the motor unit (JMA-2343: CML-645 

H-7BDRD0023 inside the scanner unit, JMA-2344: 

CBP-153) 

a. If the switches do not work even after turning the power on 

again, breakdown in the main control circuit (CMC-1156). 

b. Breakdown in the main operation panel circuit 

(CCK-873) or soft key panel circuit (CCK-872) 

c. Cut in the cable connecting the operation unit. 

216

No. Condition of the Breakdown Conceivable Cause 

5 Only noise is displayed and 

no radar image is displayed 

(characters and markers 

are, however, displayed). 

6 While radar images are 

displayed, the characters 

and markers are not 

displayed. 

a. Modulator (JMA-2343: CME-307, JMA2344: CME-308) 

b. Defective magnetron 

c. Breakdown in the main control circuit (CMC-1156) 

d. Defective tuning voltage 

a. Breakdown in the main control circuit (CMC-1156). 

7 Reception is poor. a. Deterioration or fault in the magnetron 

b. Breakdown in the modulator (JMA-2343: CME-307, 

JMA-2344: CME-308). Defect in the pulse width 

switching? 

c. Breakdown in the receiver (JMA-2343: CAE-457, 

JMA-2344: CAE-457-1) 

d. Water damage to the radiation unit or cables between 

equipment (soiling of the radiation unit, adherence of 

ice or snow, internal erosion of the cable between 

equipment) 

e. Defective tuning voltage 

f. Interruption in the pulse switching signal (PW) 

8 The image is warped or 

drifts. 

9 Nothing happens on the 

screen when the fixed 

distance marker, variable 

distance marker, electronic 

cursor or panel lighting 

switches are pushed. 

10 The screen returns to the 

initial state during operation. 

a. Breakdown or defective adjustment of the monitor 

b. Interruption in the synchronizing signal for horizontal 

signal (HS) and vertical signal (VS) 

c. Breakdown in the CRT monitor circuit (CNN-366) 

a. The brightness adjustment is at the minimum level. 

b. Breakdown in the main control circuit (CMC-1156) 

a. The electric power of the ship is inadequate. 

b. Breakdown in the main control circuit (CMC-1156) 

c. Breakdown in the power supply unit 

11 The alarm does not activate. a. Breakdown in the main control circuit (CMC-1156) 

12 The radar wake does not 

operate. 

a. Breakdown in the main control circuit 

b. The image brightness is too low. 

13 The display does not 

change to true bearing 

(north-up) or course up. 

a. There is no data being received from the bearing 

sensor (NMEA). 

217

6 After-sales Service 

★ When asking for repair 

When a system failure is suspended, read Chapter 4, 5 and 9 carefully and re-check the 

abnormal part. 

If it is still considered to be a failure, stop the operation at once and consult with the 

dealer you purchased the product, our sales department or your nearest branch or 

business office. 

● 

Repair within the warranty period 

If the failure occurred under proper operation in accordance with the instruction 

manual, the dealer or JRC shall repair the product without charging. In case of any 

other failure occurred due to mis-operation or natural disaster, the repair work will be 

charged. 

● 

Repair after the warranty period has expired 

If the product is recoverable by repairing, we will repair it upon your request. 

● 

Items to be identified 

☆ Product name, model name, manufacturing date and serial number 

☆ Failure condition (as detailed as possible: see the Radar Failure Checklist on Page 

219.) 

☆ Your company/organization name, location and telephone number 

★ Recommendation of maintenance inspection 

Although it depends on your operating condition, the performance of the product may 

be lowered due to parts wear. 

We recommend maintenance inspection, apart from the normal maintenance work. 

For maintenance inspection, consult with the dealer you purchased the product, our 

sales department, or your nearest branch or business office. 

Note that this maintenance inspection will be charged. 

For detail of after-sale service, contact the dealer you purchased the product, our sales 

department, or your nearest branch or business office. 

☞Contact : See the list at the end of the manual. 

218

RADAR FAILURE CHECKLIST 

When ordering for repair, check the following items, fill in the sheet and send it to us. 

If there is any uncertain items, contact your ship and give us correct information on the 

product. 

Ship name: Phone: Fax: 

Radar general model name:JMA― 

(Write the full model name correctly) 

Serial No.: 

(1) Check the following items in the order of the number, and circle the applicable answer 

between YES or NO. 

If the item cannot be determined as YES or NO, explain in detail in the item (15), Others. 

(2) If any of the items (1) through (4) is marked as NO, check the fuse of the product (refer 

to Section 5.6 and 9.4). 

(3) Check the items (4) through (14) while the transmission (TX) is ON. 

* Functions mentioned in the items (13) through (14) may be optional. If the function is optional, answer is not necessary. 

No. Check Item Result 

(1) Power can be turned on. (The lamp on the operation panel is lit.) YES NO 

(2) A few minutes after powering-on, it will become stand-by status (TX Ready). YES NO 

(3) When powering-on (or TX ON), the CRT displays something (CRT is lit). YES NO 

(4) 

The scanner unit rotates at the transmission (X-MIT) ON. (Check the 

following items while transmission is ON.) 

YES 

(5) Tuning is enabled. (Check with the range of 6NM or more.) YES NO 

(6) Fixed marker is displayed. YES NO 

(7) VRM is displayed. YES NO 

NO 

(8) 

White noise is displayed while set at SEA, RAIN minimum, GAIN 

maximum, IR-OFF and maximum range. 

YES 

NO 

(9) Target reflection echo is displayed. YES NO 

(10) Sensitivity of reflection echo is normal. YES NO 

(11) EBL is displayed. YES NO 

(12) Cursor mark moves. YES NO 

*(13) GYRO course can be set and normally displayed. YES NO 

*(14) LOG speed can be normally displayed. YES NO 

(15) Others (Error message, etc) 

219

7 Disposal 

7.1 Equipment Disposal 

Dispose of this equipment by following the ordinances or regulations of the local authorities 

in charge of the disposal site. 

7.2 Disposal of Used Batteries 

WARNING 

Before disposing of used lithium batteries, insulate by affixing tape to the 

positive and negative terminals or by other means. Otherwise, short-circuiting 

may occur, resulting in heat generation, bursting or ignition. 

On this equipment, lithium batteries are used for: 

BT1 in the CPU control circuit (CMC-1156) (Sanyo electric CR2032-FT6-1). 

● Do not keep used lithium batteries but dispose of them immediately after as 

non-combustible waste. 

● Before disposing of used lithium batteries, insulate by affixing tape to the positive and 

negative terminals or by other means. In the area where used batteries are separated 

from other waste, dispose of them by following the local regulations. 

7.3 Disposal of Used Magnetron 

The scanner unit in this radar use a magnetron. 

● After replacing it, return the used one to your local distributor or our sales office. 

For detail, ask your local distributor or our sales office. 

220

8 Specifications 

8.1 General 

(1) Scanning mode Raster scanning, PPI 

(2) Display unit 10-inch square monochrome CRT 

(3) Display color Green 

(4) Ranges 


0.125, 0.25, 0.5, 0.75, 1.5, 3, 6, 12, 24, 36, 48 NM 


0.125, 0.25, 0.5, 0.75, 1.5, 3, 6, 12, 24, 36, 48, 64 NM 

(5) Range resolution 25m maximum 

(6) Minimum range 25m maximum 

(7) Bearing accuracy ±1°maximum 

(8) Bearing discrimination 

JMA-2343 4.2˚ 

JMA-2344 2.2˚ 

(9) Bearing measurement mode True/Relative bearing 

(10) Environmental condition 

・ Temperature Scanner unit -15˚C to +55˚C 

Display unit -15˚C to +50˚C 

・ Relative humidity 93% maximum at 40˚C 

・ Relative wind velocity 

Scanner unit 36.0m/sec (70 knots) 

(11) Power consumption 

・ DC input (12,24,32V) 


Approx. 60W 


Approx. 65W 

・ AC input (Note) Approx. 100VA 

(100/110/115/200/220/230V, 50/60Hz single phase) 

(12) Input power range DC10.8V to DC42V 

(13) Preheating time Approx. 90 seconds 

(14) Warm-up time Approx. 3 seconds maximum 

(Note) The following rectifiers need be used when AC input is to be used : NBA-797A 

221

8.2 Scanner Unit (NKE-249/250) 

(1) Dimensions 

NKE-249 

・ Diameter 620mm 

・ Height 275mm 

NKE-250 

・ Swing circle 1220mm 


(2) Mass 

NKE-249 

Approx. 10.5kg 

NKE-250 

Approx. 24kg 

(3) Polarization Horizontal 

(4) Directivity characteristics 

NKE-249 

・ Horizontal beam width 4˚ 

・ Vertical beam width 25˚ 

・ Side lobe level -21dB maximum (less than ±10˚ from main lobe) 

NKE-250 

・ Horizontal beam width 2˚ 

・ Vertical beam width 30˚ 

・ Side lobe level -23dB maximum (less than ±10˚ from main lobe) 

-26dB maximum (other than ±10˚ from main lobe) 

(5) Rotation 

NKE-249/250 

Approx. 27 rpm 

(6) Transmitter frequency 9410±30MHz 

(7) Peak power 

NKE-249 

4kw 

NKE-250 

6kw 

(8) Transmitter tube 

NKE-249 

Magnetron : MSF1421B 

NKE-250 

Magnetron : MSF1422B 

(9) Pulse length/PRF 

NKE-249 

0.08μs /2250Hz (0.125, 0.25, 0.5, 0.75, 1.5NM) 

0.25μs/1700Hz (1.5, 3 NM) 

0.5μs/1200Hz (3, 6 NM) 

1.0μs/650Hz (6, 12, 24, 36, 48 NM) 

222

NKE-250 

0.08μs/2250Hz (0.125, 0.25, 0.5, 0.75, 1.5 NM) 

0.25μs/1700Hz (1.5, 3 NM) 

0.5μs/1200Hz (3, 6 NM) 

1.0μs/650Hz (6, 12, 24, 36, 48, 64 NM) 

(10) Modulator Solid state modulator driver 

(11) Duplexer Circulator and diode limiter 

(12) Mixer MIC front-end 

(13) IF amplifier 

・ Intermediate frequency 60MHz 

・ Band width 20/6/3MHz 

・ Characteristic Semi-log characteristic 

(14) Noise figure 6dB maximum 

223

8.3 Display Unit (NCD-4170) 


・ Width 278mm 


・ Depth 275mm 

(2) Mounting Table-top mounting 

(3) Mass Approx. 9kg 

(4) Cathode-ray tube 10-inch square monochrome CRT 

(5) Range scales Range (NM) Range ring interval (NM) Number of rings (NM) 

0.125 0.0625 2 

0.25 0.125 2 

0.5 0.25 2 

0.75 0.5 3 

1.5 0.25 6 

3 0.5 6 

6 1 6 

12 2 6 

24 4 6 

36 6 6 

48 8 6 

Only JMA-2344 64 16 4 

(6) Range ring accuracy ±0.9% of selected range or ±8m, which is greater. 

(7) VRM VRM1/VRM2 


0 to 48 NM, digital numeric display of 3 figures 


0 to 64 NM, digital numeric display of 3 figures 

(8) EBL EBL1/EBL2 

0˚ to 359˚, digital numeric display of 3 figures 

(9) Tuning mode Manual or automatic 

(10) Bearing scale 360˚ scale graduated at intervals of 1° 

(11) Ship’s heading marker Electronic 

(12) Sea surface clutter suppression Manual or automatic 

(13) Rain and snow clutter suppression Manual or automatic 

(14) Radar wakes display 15 sec/30 sec/1 min/3 min/6 min/15 min/30 min/ 

continuous 

(15) Center move 66% maximum of PPI’s radius 

224

(16) Keys/Controls 

・Main panel STBY/OFF key 

X-MIT/OFF 

STBY 

OFF 

X-MIT 

OFF 

[TUNE] control 

[GAIN] control 

[SEA] control 

[RAIN] control 

key 

RANGE 

▲ 

RANGE 

▼ 

key 

VRM 

EBL 

BRIL/HL OFF 

MENU 

ENTER 

VRM 

EBL 

MENU 

ENTER 

key 

key 

BRIL 

HL OFF 

key 

key 

key 

Cross key 

・Software key panel Software key : 4 

(17) Software key function ・DISPLAY Screen expansion [EXP] 

Center move [CENTER] 

Fixed range rings [RR] 

Cursor [CUR] 

・PROCESS Clutter suppression 

[AUTOOFF/A-SEA/A-RAIN] 

Interference rejection [IR] 

Tune mode [TUNE] 

Radar wakes [WKS] 

・GUARD Zone make [MAKE] 

Alarm setting [ALM] 

Sensitivity [SENS] 

Alarm mode [ALM] 

225

(18) Menu 

・FUNCTION 

・DISPLAY 

・RADAR SET-UP 1 

・RADAR SET-UP 2 

EBL1/VRM1 mode setting [EBL1/VRM1] 

(Fix [FIX]/Float [FLOAT]/Parallel line [PLINE]) 

EBL2 setting [EBL2] 

VRM2 setting [VRM2] 

EBL read out [EBL READOUT] 

Zooming of echo image on PPI [ZOOM] 

True motion/Relative motion [TM*/RM] 

Heading mode [HDG MODE] 

(Head-up [H-UP]/North-up [N-UP]*/ 

Course-up [C-UP]*) 

Image process [PROCESS] 

Position display [POSITION] 

(Own ship [L/L or TD]/Cursor [CUR L/L]/ 

Waypoint [WPT L/L])* 

Waypoint display [WAYPOINT] 

Range unit [RANGE] 

(NM/KY/KM) 

Timed transmission [TIMED TX] 

(Transmission period [TX PERIOD]/ 

Stand-by period [STBY PERIOD]) 

Buzzer volume [BUZZER] 

Panel dimness [DIMMER] 

Transmitter pulse width [TX PLSE] 

(1.5NM/3NM/6NM) 

Bearing reference [BEARING] 

(Magnetic bearing [MAG]/True bearing [TRUE])* 

Multi display unit setting [MULTI DISPLAY] 

Language 

(English/Japanese/Chinese/Francais/ Espanol/ 

Italiano/Norsk/Deutsch/Korea) 

226

(19) Input from external device GPS (NMEA0183) 

Electric compass or GPS compass (NMEA0183) 

NMEA0183 version : v1.5, v2.1, v2.3 

Latitude/Longitude : GGA, RMA, RMC, GLL 

Waypoint 

: RMB, BWC 

Speed 

: VTG, RMA, RMC, VHW 

Course 

: VTG, RMA, RMC 

Ship’s head : HDT, VHW, HDM, HDG 

VARIATION : HDG, RMA, RMC 

TD (LoranC time difference) : GLC, GTD, RMA 

(20) Output to external device Cursor data (Bearing/Range) 

NMEA0183 RSD sentence** 

Sub monitor 

(Vertical/Horizontal synchronous signal, 

video signal) 

* You need a connection with navigation device or bearing sensor. 

** Data output only when pushing ENTER key. 

227

8.4 Rectifier Unit (NBA-797A) 


・Width 

270mm 

・Height 

430mm 

・Depth 

175mm 

(2) Mounting Wall type, drip proof structure 

(3) Mass Approx. 18kg 

(4) Input power AC 100/110/115/200/220/230V±15% 

50/60Hz, Single phase 

(5) Power consumption 200VA 

(6) Output DC 26V, 7A 

8.5 Unit-to-unit Spacing 

Maximum Cable Length Standard Cable Length 

Scanner to display 20m 15m 

Display to rectifier (Note) 2m 

(Note) 

About power cable length between display to rectifier, see "9.5.3 Selecting 

a Long Cable" 

Attention 

• Install each equipment so that the length of the cable between a snanner unit and a 

display unit does not exceed 20m. If the regular length is exceeded, it may become 

the cause of causing poor adjustment and the defect of a system of operation. 

・The standard cables are provided with connectors and plugs. 

228

9 Installation 

This chapter has been written for the service technicians to read in case of installation. 

WARNING 

Only specialized personnel shall perform installation work. 

Installation work performed by personnel other than specialized personnel 

may cause breakdown of the equipment, poor performance, fire, severe electric 

shock and other property and human damages. 

9.1 General 

Proper installation of a radar unit is essential for extracting full capability of the unit 

reliably and for facilitating troubleshooting and maintenance. Follow the guidelines 

given below when installing the radar unit. 

(a) Install the scanner unit as high as possible while taking its weight into consideration. 

(b) Install the display unit in the wheel house for comfortable observation. 

(c) The scanner unit and display unit are connected by 10 to 20 m compound cable with 20 

conductors with an internal shield. The maximum permissible cable length is 20 m. 

Cables larger than 20 m would deteriorate the radar performance of the radar unit. 

229

9.2 Installing the Scanner Unit 

9.2.1 Selecting the installation location 

CAUTION 

The scanner unit shall be installed where there are not large obstacles in the 

direction of the ship's heading line in the same plane. 

If there is a large impediment in the same plane as the scanner unit, this may 

cause the generation of folse echoes. In particular, if such folse echoes 

appear at the ship's heading line, monitoring will be difficult and this may 

cause inadequate forecasting of danger. 

Do not install the scanner unit near chimney's or the exhaust of chimneys. 

Soot will cause the performance of the radar to decrease and heat may cause 

breakdown. 

Do not install direction antenna or VHF antenna in the vicinity of the scanner 

unit. Doing so may cause noise in the antenna reception. 

Consideration should be given to separating the radar cable from the cables 

for the direction antenna and VHF antenna. 

These cables should never be bundled into one. Doing so may cause noise 

in the antenna reception. 

9.2.2 Installation procedure 

(a) If it is found that there is no height above the roof of the wheel house enough to directly 

accommodate a scanner unit, install a pedestal or radar mast. 

(b) In addition to a pedestal or radar mast, it is necessary to provide an appropriate staging 

for convenience in installation, maintenance, adjustment, and repair of the scanner 

unit. 

230

(1) Precautions to be observed when installing the scanner unit on a power boat 

• The bow of a power boat is kept in a raised position when it is running at a high 

speed. Consequently, if the radar's scanner unit is installed horizontally when the 

boat is stopped, the following conditions will occur if the trim (elevation angle of the 

ship's bow at run time) exceeds 1/2 of the vertical beam width (θ): 

• On the front side, the water surface lies outside the beam, weakening the radio 

wave that is incident to the target on the water surface. Consequently, the 

echo generated by this target is will hardly be visible on the radar screen. 

Conversely, on the rear side: 

• Since the radio wave that is incident to the water surface is stronger, strong sea 

clutter will develop. For vessels on which the trim is 1/2 or greater than the vertical 

beam width (θ), it is recommended that the scanner unit be installed in 

such an orientation that it is tilted forwards. 

Horizontal line 

Radar scanner unit 

Beam width θ 

[When the ship is stopped or running at a slow speed] 

Beam width θ 



[High speed run: the lower part of the beam is almost horizontal.] 

231

(2) Precautions to be observed when installing the scanner unit on a yacht 

• A yacht heels on the lee side when a wind with a certain level of force blows. 

The following condition occurs if the heel angle exceeds 1/2 of the beam width: 

• On the windward side, the water surface lies outside the beam, weakening the 

radio wave that is incident to the target on the water surface. Consequently, 

the echo generated by this target is will hardly be visible on the radar screen. 

Conversely, on the lee side: 

• Since the radio wave that is incident to the water surface is stronger, strong sea 

clutter will develop. For yachts on which the heel is 1/2 or greater than the vertical 

beam width (θ) , it is recommended that the scanner unit be installed on a 

mounting base so that the scanner unit can be tilted on the left and right sides 

according to the heel angle. 

Beam width θ 

Heel angle Φ 

Wind 



232

9.2.3 Connection of cables to be assembled 

(1) Radome scanner unit (NKE-249) 

233

234

(2) Rotary scanner unit (NKE-250) 

235

9.3 Installing the Display Unit 

9.3.1 Selecting the installation location 

Attention 

• The display unit should be installed at least 1 meter from the magnet compass. 

If the display unit is installed in the vicinity of the magnet compass, the compass 

may be affected. 

Consider the following points when determining the location of the display unit: 

(a) Install the display unit in a location that provides the operator with a convenient 

viewing position. 

(b) Take after-installation maintenance into consideration. 

9.3.2 Installation procedure 

(a) Install the display unit by drilling holes using the exterior dimension drawings of the 

display unit as reference. Monitoring will be facilitated if the display is positioned so 

that the operator faces the ship's heading line (the CRT faces astern). 

(b) Wherever possible, select a location that is free of vibration. 

9.3.3 Connecting the power cable 

(a) Connect the power cable plug to the J1(POWER) connector on the rear panel of the 

display unit. 

(b) Connect the plug of the cable from the scanner unit to the J2(SC UNIT) connector on the 

rear panel of the display unit. 

● Use an adequately heavy earth cable when connecting the earth terminal of the 

display unit to the ship body. 

236

9.3.4 Display unit rear panel 

Rubber stopper 

(for connecting the optional external 

connector (J5)) 

GPS connector (J3) 

External 

connector (J4) 

EXT2 

GPS 

EXT1 

POWER 

F1 

SC UNIT 

Fuse (F1) 

Fuse (F2) 

F2 

E 

Ground terminal Power connector (J1) Cable assembly connector (J2) 

GPS connector (J3) 

1 

2 

6 

3 

5 

4 

1 +12V 

2 GND 

3 NAVCOM 

4 NAVRX 

5 NAVTX 

To GPS or LORAN 

External connector (J4) 

1 7 

2 

8 

6 

3 

4 

5 

1 DATA+ 

To cursor data input device 

2 DATA- 

3 CMPS+ 

4 CMPS- 

To electromagnetic compass/ GPS compass 

5 SVD (Image signal) 

6 SHS (Horizontal synchronization signal) 

To sub-monitor 

7 SVS (Vertical synchronization signal) 

8 GND 

237

※ The following should be used as the plug side connector for connecting to J3 and J4 

Connector Type JRC Code 

For J3 LTWD-06BFFA-L180 5JCAS00031 

For J4 LTWD-08BFFA-L180 5JCAS00027 

9.3.5 Connection of the external buzzer 

CAUTION 

Only qualified service personnel should perform external buzzer cabling work. 

Erroneous connection may cause breakdown or defective operation. 

The 5 pin connector side of the cable equipped with connector (7ZCRD0749) should be 

attached to EXT2 on the rear panel of display unit after removing the rubber stopper. The 

2 pin connector side should be connected to J5 of the display unit main control circuit 

(CMC-1156). The 3 pin connector need not be. 

Use the 5 pin connector (Type: LTWD-05BFFA-L180, JRC code: 5JCAS00030) for the plug 

side connector connected to EXT2. 

External connector J5 (5 pin) 

Attach after removing the rubber 

stopper. 

Main control circuit 

(CMC-1156) 

Power supply circuit 

(CBD-1596) 

J5 (2 pin) 

F1 

F2 

2 pin connector 

238

EXT2 Connector (J5) 

1 

2 

3 

5 

4 

1 EXTBUZ 

2 +12V 

3 

4 

5 

To external buzzer control 

Example of connection of an external buzzer 

12V relay 

LTWD-05BFFA-L180 

+12V 

to EXT2 

Protective diode 

Buzzer 

EXTBUZ 

Example of Parts 

Name Manufacturer Type JRC Code 

Relay Takamizawa LZ12H 5KLAC00033 

Diode Hitachi V06C 5TXAE00016 

239

9.3.6 Connecting an electromagnetic compass 

Attention 

• Ensure that the output of the inboard power supply and rectifier unit and connection to 

the power cable is correct. 

Erroneous connection or voltage may cause breakdown. 

It is possible to input information on bearing to the radar display unit if you use the electromagnetic 

compass with a NMEA0183 output terminal. 

(It is impossible to connect if you use the electromagnetic compass without a NMEA0183 

output terminal.) 

(1) Solder the data cable of electromagnetic compass (with NMEA0183 output) to the 8 pin 

connector. The polarity is as shown below and care should be taken in making this 

connection. 

8 pin connector (pin 3) Electromagnetic compass data (+) 

8 pin connector (pin 4) Electromagnetic compass data (-) 

Type of LTWD-08BFFA-L180 (JRC code: 5JCS00027) should be used as the 8 pin 

connector. 

• Unless the connection between the 8 pin connector and data cable is correct, 

correct data will not be obtained. 

(2) Connect the 8 pin connector to J4 (EXT1) on the rear panel of the display unit. 

EXT2 

GPS 

EXT1 

Electromagnetic compass 

F1 

POWER 

SC UNIT 

F2 

E 

J4 

Radar display unit rear panel 

1 7 

2 6 

3 5 4 

8 

Data - 

Data + 

8P connector (black) 

This completes the cabling of the electromagnetic compass. 

240

9.4 Modifications to be Made to the Inboard Power Supply 

Attention 

• Be sure to use the correctly rated fuse. In the event incorrectly rated fuse is used, 

this may cause breakdown in the equipment. 

• Make modifications as shown below based on the inboard power supply. 

(Fuse for 24V is incorporated upon shipment of the equipment) 

1. Display unit 

Fuse rating 

F1 

F2 

Inboard power supply Rating JRC Code Rating JRC Code 

DC12V 6.3A 5ZFAD00336 10A 5ZFAD00539 

DC24/32V 3.15A 5ZFAD00227 5A 5ZFAD00364 

2. Scanner unit 

No modifications need to be made with respect to the scanner unit. 

241

9.5 Cable Assemblies 

9.5.1 Inter-unit cable (CFQ6774-10/15/20, CFQ6882-10/15/20) 

(a) This cable is used to connect the display unit to the scanner unit. 

(b) Use the following cables with connectors for this radar equipment. 

Cable length JRC Code for JMA-2343 JRC Code for JMA-2344 Remarks 

15m 

CFQ6774-15 

CFQ6882-15 

Standard 

10m 

CFQ6774-10 

CFQ6774-10 

Option 

20m 

CFQ6774-20 

CFQ6882-20 

Option 

Color 

Number of Conductors/Diameter 

Signal Name 

(mm) 

Shielded wire (conductor) : Black 7/0.20 TI 

Shielded wire (shield) 

TIE 

Co-axial cable (conductor) 7/0.20 VD 

Co-axial cable (shield) 

VDE 

Red (Thick) 50/0.18 1A 

Yellow (Thick) 50/0.18 1A 

Blue (Thick) 50/0.18 2A 

Purple (Thick) 50/0.18 2A 

Green (Thick) 50/0.18 1A 

Pink (Thick) 50/0.18 1A 

Gray (Thick) 50/0.18 2A 

Brown (Thick) 50/0.18 2A 

Orange (Middle thick) 34/0.18 BP 

Green 7/0.20 BZ 

Yellow 7/0.20 COM+ 

Twisted pair 

White 

7/0.20 COM- 

※The outside diameter size of the cable :11.5±0.5 [mm] 

Only JMA-2344 

242

9.5.2 Power cable (CFQ-6776) 

The radar unit is provided with a 2 m power cable with connectors 

Color 

Number of Conductors 

/Diameter 

Cross Section 

(mm 2 ) 

Polarity 

White 50/0.18 1.25 + 

Black 50/0.18 1.25 - 

Attention 

• Ensure that the output of the inboard power supply and rectifier unit and connection to 

the power cable is correct. 

Erroneous connection or voltage may cause breakdown. 

9.5.3 Selecting a long cable 

• The effective voltage of the input to the radar is the voltage at the inboard power 

supply minus the voltage drop caused by the power cable. Too thin or long a 

power cable incurs a large voltage drop and may not be able to supply adequate 

power to the radar. In is recommended that the following guidelines be observed 

when selecting the power cable for your radar: 

(a) Consider the possible voltage regulation of the inboard power supply (Vs). 

(b) Use the following equation to calculate the voltage drop: 

V=2LRKI 

L:represents the cable length. 

R:represents the direct-current resistance (/m) at 20 

K:represents the conductor resistance temperature coefficient (= 1.22) 

I :Maximum peak current (A) 

(c) The table below lists the direct-current resistance (R) and permissible current 

(Imax) of several cables. 

Cable Type R (20℃) Imax (45℃, continuous) 

CVVS2×1.25 16.7 Ω.km 13A 

CVVS2×2.0 9.42 Ω/km 19A 

CVVS2×3.5 5.30 Ω/km 26A 

The cable to be used must possess a sufficient permissible current (Imax) characteristic. 

243

9.6 After-installation Adjustments 

9.6.1 Installation-time check 

(a) After completing the installation procedure, it is necessary to check the radar unit to 

verify that all installation steps have been conducted as instructed. In particular, 

check for correct cabling, for normal component operating state, for water leakage in the 

scanner unit, and for proper grounding of braided shielding cable. 

9.6.2 Functional checks 

(a) After completing the installation-time check and before checking the operation of the 

radar, make sure that the output voltages of the inboard power supply fall within their 

permissible range. 

(b) Read "3 Basic Operation" carefully and thoroughly and make sure that the radar 

functions normally. Then, manipulate all controls and menu functions to ensure that 

they function normally. 

(c) If it becomes necessary to make an adjustment though the radar unit is normal, read 

"9.7 Adjustment Procedures" carefully and follow the instructions given in that section. 

9.6.3 Adjustment items 

(a) Radar's bearing adjustment is mandatory. 

(b) If the control is not positioned near the center of the scale during tuning or if tuning fails, 

make a coarse tuning from the "TUNE PRESET" menu. 

(c) If there is a difference between the range displayed on the radar's PPI screen and the 

actual range, adjust the range from the "DISPLAY TIMING" menu. 

(d) The "BUZZER" menu can be used to adjust the volume of the alarming buzzer. 

(e) The "STC PRESET" menu can be used to adjust the STC. 

244

9.6.4 Rectifier unit 

● The rectifier unit can run on inboard voltages of 100/110/115 VAC and 200/220/230 

VAC provided that connections at the input terminals on the NBA-797A T701 are 

changed. The figures below show how to change the connections at the input terminals. 

Reconnect according to the input voltage. 

Reconnect according to the input voltage. 

115V 

110V 

100V 

230V 

220V 

200V 

This terminal must not be reconnected. 

This terminal must not be reconnected. 

100/110/115 VAC 200/220/230 VAC 

[Reconnecting the NBA-797A input terminals] 

245

9.7 Adjustment Procedures 

9.7.1 General adjustments 

1. Adjustments to be made when a part is replaced 

Adjustments need to be performed when major parts of the radar unit. are replaced. 

(a) When the V101 magnetron is replaced 

(b) When the E101 front end is replaced 

Tuning 

Tuning 

(c) When the V901 Cathod-ray tube is replaced * 

Off center adjustment 

When the CRT monitor PCB is replaced 

Brilliance level adjustment 

Focus adjustment 

*: When exchanging V901 (CRT), the Direction coil implement in the stuck condition. 

Incidentally, It is possible to arrange in cathode-ray tube monitor chassis (CKJ-159) 

2. CRT monitor off center adjustment 

(a) This adjustment must be performed on the centering magnet (permanent magnet) 

located immediately behind the deflection coil. This permanent magnet is made up of 

two doughnut-like disks. 

(b) Turn the centering knob so that the neck of the Cathod-ray tube is in alignment with the 

center of the PPI screen. 

3. Adjusting the brilliance level of the CRT monitor screen. 

(a) Set the brilliance level of the CRT monitor screen to its maximum from the menu. 

● Please refer to "3.2.1 Changing the brightness of the screen" for the method of adjustment. 

(b) Turn potentiometer R451 on the CRT monitor PCB so that no raster appears in the 

non-displayable area. (Turn the potentiometer slowly since the circuit's sensitivity is 

very high.) 

4. Adjusting the focus of the CRT monitor screen 

(a) Turn potentiometer R951 on the neck PCB in the display unit so that the range rings 

and video images appear most clearly. 

246

9.7.2 Adjusting the scanner unit 

The scanner unit has several locations that need adjustment. They are factory set and 

normally need not be adjusted by the user. If it is necessary to make functional checks 

during inspection or repair, make the adjustments that are explained below. 

WARNING 

Hi-voltage Caution 

High-tension voltages of 4,000 volts or higher are present at the modulator 

units (CME-307 or CME-308). The modulator unit must be accessed only by 

qualified service engineers. 

Inadvertent manipulation may result in severe electric shock. 

1. Adjusting the AVR output voltage from the modulator 

(a) Place the radar unit into the transmission state (the range scale set to 12NM), connect a 

VOM across J203-14PIN on the CME-307 or CME-308 and the GND terminal, and 

adjust RV2 so that the output voltage reads +8 volts. 

2. Adjusting the tuning indicator level of the receiver 

(a) If the tuning mode is set to "AUTO", reset it to "MANUAL". 

(b) Tune the receiver with the range scale set to 12 NM. 

9.7.3 Adjusting the display unit 

The display unit has several locations that need adjustment. They are factory set and 

normally need not be adjusted by the user. If it is necessary to make functional checks 

during inspection or repair, make the adjustments that are explained below. 

1. Adjusting the brilliance level 

(a) Set the brilliance level of the screen to its maximum from the [BRIL] key. 

(b) Turn potentiometer R451 on the CRT monitor PCB so that no raster appears in the 

non-displayable area. (Turn the potentiometer slowly since the circuit's sensitivity is 

very high.) 

2. Adjusting the focus of the CRT monitor screen 

(a) Turn potentiometer R951 on the neck PCB in the display unit so that the range rings 

and video images appear most clearly. 

247

3. Adjusting the tilt angle of the display unit 

(a) The angle of the screen can be adjusted by loosening the lock screw on the deflection coil 

assembly at the neck of the CRT tube and turning the entire screen. The user can also 

adjust the screen position using the centering magnet. 

4. Adjusting the CRT display 

In addition to adjustment steps 1. to 3. explained above, CRT monitor adjustments include 

the following: 

(a) Horizontal level adjustment 

(b) Vertical size adjustment 

(c) Contrast adjustment 

(d) Focus adjustment 

CCN-366, L400 

CCN-366, R353(V. SIZE) 

CCN-366, R451(CONT) 

CCN-366, R951 

WARNING 

Hi-voltage Caution 

The CRT monitor (CCN-366) generates high electric voltage about 10kV and 

on service personnel should touch parts inside the display. 

Inadvertent manipulation may result in severe electric shock. 

5. Adjusting the AVR output voltage 

(a) Connect a high-precision voltmeter across pin TP1+3.3V on the CBD-1596 power supply 

and the chassis, adjust potentiometer +3.3ADJ so that the output voltage reads +3.3± 

0.02V. 

Attention 

● Be sure to connect the scanner unit when making this adjustment. 

248

9.8 Initial Settings 

This section will explain the method of initial setting of the radar unit. Initial setting 

needs to be undertaken prior to initial use. 

Initial setting includes: 

(a) INITIAL SETTING 1 

• Tuning preset (TUNE PRESET) 

• Bearing adjustment (BEARING) 

• 0 NM adjustment (DISPLAY TIMING) 

• Main bang suppression level (MBS LEVEL) 

• Main bang suppression range (MBS RANGE) 

• Sensitivity preset (GAIN PRESET) 

• Comparator preset (COMPARATOR PRESET) 

• Sea surface clutter preset (STC PRESET) 

• Antenna height preset (ANTENNA HEIGHT) 

• GPS preset (GPS PRESET) 

(b) INITIAL SETTING 2 

• Setting the TD reception number (SET TD NUMBER) 

• Simulator image display (SIMULATOR) 

Attention 

• Be sure to undertake initial setting prior to initial use. 

• Unless initial setting has been undertaken, it is not possible to display the target or 

measure the distance or bearing of a target correctly. 

• INITIAL SETTING 1, the initial setting menu that is used here, is displayed by 

pushing the ENTER key and MENU key simultaneously. 

249

9.8.1 Adjustment of the receiver 

• This adjustment need not be changed in general as the equipment is adjusted 

ex-factory. 

• If the adjustment is changed inadvertently, it will not be possible to obtain the optimum 

tuning even when the TUNE control is operated. 

1. Tune preset 

Here, rough adjustment of the tune will be undertaken. 

(a) Set the range to 12NM pushing the "▲(up)" or "▼ (down)" on the 

RANGE 

key. 

(b) Push the soft key 

PROCESS . 

(c) Push the soft key 3 and select 

M-TUNE . 

The method of tuning has been set to "manual". 

(If the mode is already in manual tuning, this operation is not required.) 

(d) Push the 

MENU 

key and close the soft key menu. 

(e) Push the 

X-MIT/OFF 

switch and wait for 10 minutes or more. 

Transmission will begin. 

After about 10 minutes, the transmission frequency will stabilize. 

(f) Turn the [TUNE] control to the mid position. 

(g) Select "TUNE PRESET" in the line "RECEIVER ADJUST" - the menu "INITIAL 

SETTING 1". 

(h) Pushing the "▲ (up)" or "▼ (down)" on the 

the PPI image becomes the maximum size. 

RANGE 

key, adjust so that 

(i) Push the 

ENTER 

key. 

The adjustment has been completed. 

250

2. Adjusting the central frequency 

Adjustment is undertaken so that the image is largest when the deflection of the tune 

level indicator is at the maximum. 

(a) Undertake operations (a) through (e) of "1.Tune Preset". 

(b) Adjust the image to the maximum using the [TUNE] control. 

(c) Select "TUNE FREQUENCY" in the line "RECEIVER ADJUST" - the menu 

"INITIAL SETTING 1". 

(d) Adjust to maximize the deflection of the tune level indicator pushing the "▲ (up)" 

or "▼ (down)" on the 

RANGE 

key. 

(e) Push the 

ENTER 

key. 


3. Adjusting the level of the tune level indicator 

Adjust the scale to correspond to the maximum deflection of the tune level indicator bar. 

(a) Undertake operations (a) through (e) of "1.Tune Preset". 

(b) Using the [TUNE] control, adjust to maximize the deflection of the tune level indicator. 

(c) Select "TUNE LEVEL IND" in the line "RECEIVER ADJUST" - the menu "INI- 

TIAL SETTING 1". 

(d) Adjust so that the deflection of the tune level indicator is 80% to 90% of the 

indicator area pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

key. 

(e) Push the 

ENTER 

key. 


251

9.8.2 Adjusting the noise level 

This operation adjusts the basic level of the echo that is displayed on the PPI screen. 

Attention 

• This adjustment need not be changed in general as the equipment is adjusted ex 

factory. 

• If the adjustment is changed inadvertently, it will not be possible to obtain optimum 

images as a phenomenon causing reduction in sensitivity may be generated. 

(a) Select "COMPARATOR PRESET" in the menu "INITIAL SETTING 1". 

(b) Adjust the noise level pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

key. 

(c) Push the 

ENTER 

key. 

The noise level adjustment has been completed. 

9.8.3 Adjusting the bearing 

This operation adjusts the bearing on the PPI screen. 


If the mode is already in RM, this operation is not required. 

(b) Select "H-UP" in the line "HDG MODE" - the menu "FUNCTION". 

If the mode is already in H-UP, this operation is not required. 

(c) Determine the target. 

Select an image of a target within 1NM to 2NM that can be seen with the naked eye and 

that is not moving. 

(d) Measure the bearing of the target from the ship's bow using the ship's compass. 

For example, assume the target is stationary at a bearing of 25 degrees from the ship's bow. 

(e) Select "BEARING" in the menu "INITIAL SETTING 1". 

The EBL for bearing adjustment will be displayed. 

This EBL is different from #1EBL or #2EBL. 

252

(f) Push the cross key, and align the EBL to the image of target's echo. 

(g) Push the 

ENTER 

key. 

(h) Using the cross key, align the EBL to the bearing of the target measured in (d). 

The PPI screen also rotates with the EBL. 

(i) Push the 

ENTER 

key. 

The bearing adjustment has been completed. 

9.8.4 0 NM adjustment (Initial setting of distance) 

This operation is for calibrating distance on the PPL screen. 


If the mode is already in RM, this operation is not required. 

(b) Select "H-UP" in the line "HDG MODE" - the menu "FUNCTION". 

If the mode is already in H-UP, this operation is not required. 

(c) Adjust the range to 0.125NM pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

key. 

(d) Determine the target. 

Select a target from among echo image on the PPI with respect to which the distance 

from the ship is known. 

In this case, it is assumed that a stationary target 0.08NM from the ship has been selected. 

(e) Push the 

VRM 

key. 

#1VRM/#2VRM will be displayed. 

In the event #1VRM is to be used, select "FIX" in the line "EBL1/VRM1" - the menu 

"FUNCTION". 

(f) Using the up and down functions of the cross key, adjust the VRM to the distance to the target. 

Adjust to the actual distance to the target. 

(g) Push the 

ENTER 

key. 

(h) Select "DISPLAY TUNING" in the menu "INITIAL SETTING 1". 

253

(i) Adjust the proximate perimeter of the target to the distance to the VRM pushing the "▲ 

(up)" or "▼ (down)" on the 

RANGE 

key. 

(j) Push the 

ENTER 

key. 

The 0 NM adjustment has been completed. 

Reference: When there is no target with known distance from the ship. 

If there is no target with known distance from the ship, it is possible to undertake 0 NM 

adjustment using the following simplified method. 

(A) Steps (a) through (c) are the same as with a target of known distance. 

(B) Select a target that represents a long linear line such as the shoreline or embankment. 

(C) Same as in (h) with a target of known distance. 

(D) Adjust so that the target becomes a straight line on the PPI screen pushing the "▲ 

(up)" or "▼ (down)" on the 

RANGE 

key. 

Position of the ship 

Ship's heading marker 

Target 

The distance is too great The distance is just right The distance is too short 

(E) Push the 

ENTER 

key. 

The 0 NM adjustment has been completed. 

9.8.5 Setting the antenna height 

This operation sets the height of the antenna from the sea surface. 

(a) Select "ANTENNA HEIGHT" in the menu "INITIAL SETTING 1". 

254

(b) Select the height of the radar antenna among "UNDER 5m", "5m TO 10m", and "MORE 

THAN 10m". 

9.8.6 Presetting the sensitivity 

This operation sets the maximum sensitivity when [GAIN] control is turned. 

This adjustment should not be undertaken without reason. 

When undertaking this adjustment, also undertake "9.8.2. Adjustment of the Noise Level". 


DISPLAY . 


EXP OFF . 

(c) Turn the [RAIN] control to the minimum (turn to maximum counterclockwise). 

(d) Turn the [SEA] control to the minimum (turn to maximum counterclockwise). 

(e) Turn the [GAIN] control to the maximum (turn to maximum clockwise). 

This maximizes the strength of the echo on the PPI screen. 

(f) Select "GAIN PRESET" in the menu "INITIAL SETTING 1". 

(g) Adjust the sensitivity level pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

key. 

(h) Push the 

ENTER 

key. 

The maximum level of gain has been set. 

9.8.7 Presetting the sea clutter 

This operation sets the maximum level of suppression when the [SEA] control is turned. 

This adjustment should not be undertaken without reason. 

(a) Set the range to 0.125NM pushing the "▼ (down)" on the 

RANGE 

key. 

(b) Undertake tuning adjustment using the [TUNE] control. 

(c) Push the soft key 

DISPLAY . 

255

(d) Push the soft key 1 and select 

EXP OFF . 

(e) Turn the [GAIN] control to the maximum (turn to maximum clockwise). 

(f) Turn the [RAIN] control to the minimum (turn to maximum counterclockwise). 

(g) Turn the [SEA] control to the maximum (turn to maximum clockwise). 

The strength of the echo on the PPI screen is maximized with sea surface clutter suppression 

maximized. 

(h) Select "STC PRESET" in the menu "INITIAL SETTING 1". 

(i) Adjust the level of suppression pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

The PPI screen near the center adjusts to the grade projected slightly. 

key. 

(j) Push the 

ENTER 

key. 

Suppression of sea surface clutter has been set at the maximum level. 

9.8.8 Suppression of main bang 

This adjustment is undertaken to suppress main bang that is the reflected signal from 

three dimensional circuits such as the wave guide that normally appears at the center of 

the radar display as a circle. 

Optimum adjustment is achieved when the main bang image remains lightly on the 

screen. 

Attention 

• This adjustment should not be undertaken without reason. Erroneous adjustment 

may cause targets that are proximate to be erased from the screen. 

(a) Set the range to 0.125NM pushing the "▼ (down)" on the the 

RANGE 

key. 

(b) Select "OFF" in the line "PROCESS" - the menu "FUNCTION". 

(c) Push the soft key 

DISPLAY . 

256

(d) Push the soft key 1 and select 

EXP OFF . 

(e) Push the the soft key 

PROCESS . 

(f) Push the soft key 1 and select 

AUTO OFF . 

(g) Turn the [GAIN] control to the maximum (turn to maximum clockwise). 

(h) Turn the [SEA] control to the mid position. 

(i) Turn the [RAIN] control to the minimum (turn to maximum counterclockwise). 

(j) Select "MBS LEVEL" in the menu "INITIAL SETTING 1". 

(k) Adjust the suppression level pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

key. 

(l) Push the 

ENTER 

key. 

The suppression level of the main bang has been determined. 

(m) Select "MBS RANGE" in the menu "INITIAL SETTING 1". 

(n) Adjust the suppression range pushing the "▲ (up)" or "▼ (down)" on the 

RANGE 

key. 

(o) Push the 

ENTER 

key. 

Adjustment of the suppression range of the main bang has been completed. 

9.8.9 Display of simulator image 

By activating this function, it is possible to display a demonstration screen on the PPI 

screen. 

• To make the setting of this function effective, the power must be once switched off. 

(a) Push the 

STBY/OFF 

key. 

The display will enter the standby mode. 

257

(b) Select "INITIAL SETTING 2" in the menu "INITIAL SETTING 1". 

(c) Select "ON" in the line "SIMULATOR" - the menu "INITIAL SETTING 2". 

9.8.10 Setting the TD reception number 

This operation is for selecting the number of the TD (LORAN C time difference) to be 

received. 

(a) Select "INITIAL SETTING 2" in the menu "INITIAL SETTING 1". 

(b) Move the cursor to the extent of the value shown in the "SET TB NUMBER" - the menu 

"INITIAL SETTING 2". 

(c) Move the location for input by operating the left and right keys of the cross key. 

(d) Select the TD number to be received pushing the "▲ (up)" or "▲ (down)" 

on the 

RANGE 

key. 

When the numbers are selected, the following field data of NMEA is displayed. 

1: TD1 field of the GTD/GLC sentence. 





A: A field of the RMA sentence 

B: B field of the RMA sentence 

258

9.8.11 GPS/DGPS 

1. Initial setting of GPS 

This operation is for undertaking initial setting of GPS. The GPS receiver measures position 

without initial setting but 10 or more minutes may be required after initial setting. 

● Content of settings 

Ship position : Approximate latitude and longitude is sufficient 

Exclusion satellite : When unhealth satellite is used, precision may deteriorate. 

The satellite number input here is not used for measuring the 

position. 

Geodetic system : Japan is "02" 

Antenna height : Input the height of the antenna from the sea surface. 

Fix mode 

: Since the height of the antenna is fix in the case of an ocean 

going vessel, greater stability in position is obtained in 2D (two 

dimensions). 

DOP level : If only position results with high precision are intended to be 

used, designate 10 or less or 5 or less. 

Position average : When variance in position needs to be minimized, select LONG . 

When response needs to be maximized select 

NONE 

. However, 

with this latter setting, variance will increase. 

(a) Select "GPS" in the line "GPS PRESET" - the menu "INITIAL SETTING 1". 

The menu "GPS" will be displayed. 

(b) Select the items in the cross key and change the set value using the 

RANGE 

key. 

In order to change the ship's "N/S" or "E/W" position using the left and right keys 

of the cross key. 

(c) Push the 

ENTER 

key. 

The setting has been determined. 

(d) Select "SEND DATA" in the menu "GPS". 

The GPS setting will be implemented. 

2. Initial setting of DGPS 

In the event high precision position determination is intended using DGPS, it is necessary 

to set the beacon receiver. 

259

● Setting mode 

MANUAL : This operation sets the frequency and baud rate of the beacon receiver. 

This allows receipt of DGPS at an early stage but receipt is not possible 

unless the ship is in the beacon receipt area that is set. 

AUTO : Automatic search of the beacon transmission station is undertaken for 

receipt. Time is required for this search. 

(a) Select "DGPS" in the line "GPS PRESET" - the menu "INITIAL SETTING 1". 

The menu "DGPS PRESET" will appear. 

(b) Select the items in the cross key and change the set value using the 

RANGE 

key. 

Changing "N/S" and "E/W" of the ship's position is also set pushing the "▲ (up)" 

or "▼ (down)" on the 

RANGE 

key. 

(c) Push the 

ENTER 

key. 

The setting has been determined. 

(d) Select "SEND DATA" in the menu "DGPS PRESET". 

The DGPS setting will be implemented. 

3. Status of reception of GPS and DGPS 

This operation displays the status of reception of the GPS receiver and DGPS receiver. 

(a) Select "CONDITION" in the line "GPS PRESET" - the menu "INITIAL SETTING 1". 

The status of reception of the GPS receiver and DGPS receiver will be displayed. 

The display of the reception status of GPS will display the conditions of the following items 

only when the sensor type receiver such as JLR-4310 is connected and operating normally. 

● Items 

Ship position : When the ship's position is determined, the latitude and longitude 

of the position will be displayed. 

GPS internal time : The world time as measured by the GPS receiver will be displayed. 

Altitude 

: The altitude of the ship will be displayed. However, when 

the fix mode is 2D (two dimension), the height of the antenna 

that was input at initial setting will be displayed. 

DOP 

: The precision of the results of the measurement will be displayed. 

If the value is 20 or above, the precision is poor. 

260

Reception satellite : The number of the satellite used for the measurement will be 

displayed. 

Bearing, elevation angle : The bearing and elevation angle of the satellite will be displayed. 

Signal strength : The strength of the signal of the satellite from which signals 

are being received will be displayed. If the value is 20 or 

less, the satellite may not be usable for measurements. 

The following items will be displayed only when a beacon receiver is connected and 

operating normally. 

● Items 

Frequency 

: The frequency of the beacon station from which signals are 

being received will be displayed. 

Baud rate 

: The baud rate of the beacon station from which signals are 

being received will be displayed. 

RSSI 

: The reception strength of the beacon station from which signals 

are being received will be displayed. If the value is 100 

or less, the beacon may be not possible to receive signals. 

261

List of Geodetic Systems 

No. 

Name 

0 WGS-84 

1 WGS-72 

2 Japan 

3 North American 1927 (U.S) 

4 North American 1927 (Canada & Alaska) 

5 European 1950 (Europe) 

6 Australian geodetic 1966 (Australia) 

7 Ordance Survery of Great Britain (England) 

8 NAD-83 

9 - (no use) 

10 - (no use) 

11 ADINDAN (Etiopia & Sudan) 

12 ARC 1950 (Botswana) 

13 AUSTRALIAN GEODETIC 1984 (Australia) 

14 BERMUDA 1957 (the Bermudas) 

15 BOGOTA OBSERVATORY (Columbia) 

16 CAMPO INCHAUSPE 

17 CHATHAM 1971 

18 CHUA ASTRO (Paraguay) 

19 CORREGO ALEGRE (Brazil) 

20 DJAKARTA (VATAVIA) (Sumata) 

21 EUROPEAN 1979 (Europe) 

22 GEODETIC DATUM 1949 (New Zealand) 

23 GUAM 1963 (Guam) 

24 HAYFORD 1910 (Finland) 

25 HJORSEY 1955 (Ice land) 

26 INDIAN (India & Nepal) 

27 IRELAND 

28 KERTAU 1948 (West Malaysia) 

29 L.C.5 ASTRO (Cayman Black Island) 

30 LIBERIA 1964 (Liberia) 

31 LUZON (Philippines) 

32 MERCHICH (Morocco) 

33 MINNA (Cameroon) 

262

34 NAHRWAN (Oman) 

35 NAPARIMA, BWI (Trinidad and Tobago) 

36 OLD EGYPTIAN (egypt) 

37 OLD HAWAIIAN (the Hawaii Island) 

38 PICO DE LAS NIEVES (the Canary Island) 

39 PROVISIONAL SOUTH AMERICAN 1956 (South America) 

40 PROVISIONAL SOUTH CHILEAN 1963 (Southern Chile) 

41 PUETRO RICO (Puerto Rico and V irgin Island) 

42 QORNOQ (South Greenland) 

43 RT90 (Sweden) 

44 SANTA BRAZ (Sao Maguel, Santa Maria Island) 

45 SOUTH AMERICAN 1969 (South America) 

46 SOUTHWEST BASE (Faial,Graciosa,Pico,Jorge and terceira Island) 

47 TIMBALAI 1948 (Brunei and East Malaysia) 

263

9.9 Returning to the Initial Setting Conditions 

In the event such phenomena as the distorted screen or the keys becoming inoperable 

occurs while the radar is in use, the following procedures shall be taken to initialize the 

system. 

Attention 

• When initialization is undertaken, all setting excluding the menu "INITIAL SET- 

TING 1" and "INITIAL SETTING 2" will be reset to the ex-factory shipment conditions. 

(a) Push the 

STBY/OFF key and X-MIT/OFF 

Power is turned off. 

key simultaneously. 

(b) Push the 

MENU key, ENTER key and STBY/OFF 

simultaneously. 

Power will be turned on as in normal operation for turning on power. 

key 

264

9.10 Maintenance 

9.10.1 General maintenance 

It is necessary to perform the maintenance services listed below to keep the radar unit 

in good working conditions. Proper maintenance of the radar unit minimizes the possibility 

of machine failures. The maintenance operations that are common to all components 

of the radar unit are listed below. 

1. Cleaning 

Remove dirt, dust, or water-spray from the radar unit enclosure and keep it as clean as 

possible. Use a dry lint-free cloth. 

2. Screw inspection 

Check the screws used to assemble and secure the components of the radar unit for 

loose connection. 

3. Cabling check 

Check the cables connecting between the components (between the scanner unit and 

display unit, display unit and power supply, and display unit and optional devices) for 

poor connection. 

WARNING 

Before starting maintenance work, be sure to turn off the main power source. 

If a rectifier unit is used, in particular, turn off power to the display unit. Note 

that voltages from the rectifier unit are always present even if the radar is 

stopped. It may result in sereve electric shock or breakdown. 

265

9.10.2 Scanner unit 

WARNING 

When performing maintenance or inspection of the scanner unit, be sure to 

shut off the safety switch of the scanner unit after turning off the power of the 

display unit. Failure to do this may cause severe electric shock or 

breakdown or the sudden movement of the scanner unit may cause bodily 

injury or breakdown. 

CAUTION 

Since the magnetron in the modulator circuit emits strong magnetism, watches 

or magnetic cards should not be brought into close proximity of the modulator 

circuit. Doing so may cause breakdown and destruction of data contained in 

such items. 

1. Radiation unit 

(a) A radiation surface of radiation unit (JMA-2343: Whole surface of the radome cover / 

JMA-2344: Front side of radiation unit) contaminated by smoke, dust, or paint would 

cause attenuation or reflections of radio waves, resulting in reduced radar performance. 

Periodically check the radome scanner unit. If it proves dirty, wipe the radome surface 

with a soft lint-free cloth moistened with alcohol or damped cloth. 

CAUTION 

Never use such solvent as Thinner, Gasoline, Benzen, Trichlene or Kentene 

for cleaning. Those solvents deteriorate the surface. 

266

2. Rotary drive block (JMA-2344) 

(a) Lubricating gears 

Apply grease to gears evenly using a knife or brush. This lubrication needs to be performed 

at least semiannually. The shorter the lubrication period, the longer the gears will 

endure. 

Use Mobilux 2 from Mobile Oil Co., Ltd. or equivalent. 

(b) Drive motor (JMA-2344) 

(α) Reduction gears 

The reduction gears need no lubrication unless it is subject to oil leakage. If 

they are disassembled for overhaul, replenish lubricant "Beacon 325" from Esso 

Standard. 

(β) Motor 

The life time of the brush unit is 2,000 hours. The brush needs to be replaced if 

1/2 of the overall length is worn. 

The commuter needs to be kept clean. If any carbon power fixed on the commuter 

cannot be removed with a dry cloth, burnish it with a sand paper # 150 to 

#400. 

The carbon brush can be removed by removing the caps located on both sides of 

the bottom portion of the motor. 

Contact with the commuter 

Spring 

Carbon brush 

Description Type JRC code Quantity 

Carbon Brush 54531-01 BRXP05247 2 

(c) Pedestal 

Check the scanner unit mounting molts occasionally and apply paint semiannually to 

protect them from corrosion. 

267

9.10.3 Display unit 

Cleaning the Display Unit Screen 

● Dust on the CRT tube would reduce the glass transparency and make the vide 

image dim. Wipe the screen surface with a soft lint-free cloth (made of flannel or 

cotton). A cloth moistened with an antistatic agent would cause little problem. 

When using it, wipe softly; never rub the screen surface with force. 

268

For further information contact : 

HEAD OFFICE & 

SALES DEPT. 

MAIN PLANT 

Akasaka Twin Tower (Main), 

17-22, Akasaka 2-chome, Minato-ku, 

Tokyo, 107-8432 JAPAN 

Phone : +81-3-3584-8711 

Fax : +81-3-3584-8715 

Telex : 0242-5420 JRCTOK J 

1-1, Shimorenjaku 5-chome, Mitaka-shi, 

Tokyo 181-8510 JAPAN 

Phone : +81-422-45-9111 

Fax : +81-422-45-9110 

Telex : 02822-351 JRCMTK J

JMA-2343/2344 - ProNav

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