Furuno 841 MARK-2 - Manuals

v FOREWORD ................................ v SPECIFICATIONS ..................... vii EQUIPMENT LIST ...................... ix CONFIGRATION ......................... xi 1. PRINCIPLE OF OPERATION ............................. 1 1.1 What is Radar? ................................. 1 1.2 How Ships Det...

vi Congratulations on your choice of theFURUNO MODEL 841 MARK-2 MarineRadar. We are confident you will see whythe FURUNO name has become synony-mous with quality and reliability. For over 40 years FURUNO Electric Com-pany has enjoyed an enviable reputation forinnovative and dependable marine electro...

vii Antenna Unit 1. Radiator Printed array 2. Radiator length 54 cm 3. Horizontal beamwidth 3.9 ° 4. Vertical beamwidth 20 ° 5. Sidelobe -20 dB within main lobe-23 dB outside main lobe 6. Polarization Horizontal 7. Antenna rotation speed 24 rpm 8. Wind resistance Relative wind speed 100 kts (51.5 m/...

viii Stand-by (ST-BY), Echo Trail Time(TRAIL), Variable Range Marker(VRM), Range, Range Ring Interval,Range and Bearing to Cursor (+), OffCenter (OFF CENTER), Watchman(WATCHMAN)With navigation input (option): Course(CRS), Latitude and longitude, Speed(SPD), Range and bearing to waypoint(WP), Cross T...

ix EQUIPMENT LIST Complete Set . o N e m a N e p y T . o N e d o C y t Q s k r a m e R 1 t i n u a n n e t n A 8 5 0 - 1 7 0 0 - B S R 1 2 t i n u y a l p s i D 2 M 4 - 3 1 1 - P D R 1 3 s t r a p e r a p S 0 0 8 9 0 - 3 0 P S 1 4 4 - 5 8 0 - 0 0 0 t e s 1 4 s e i r o s s e c c A 0 0 9 5 0 - 3 0 P F...

x Optional Equipment . o N e m a N e p y T . o N e d o C y t Q s k r a m e R 1 r e i f i t c e R 2 6 - R P 4 8 4 - 3 1 0 - 0 0 0 1 C A V 0 0 1 5 8 4 - 3 1 0 - 0 0 0 C A V 0 1 1 6 8 4 - 3 1 0 - 0 0 0 C A V 0 2 2 7 8 4 - 3 1 0 - 0 0 0 C A V 0 3 2 2 r e z z u B l a n r e t x E 6 3 1 - 3 0 P O 3 4 4 - 6...

xi 5A NAV Video Sounder Gyro Gyro Converter AD-100 *Equivalent to NMEA0183 Option IEC 1162* IEC 1162* (In/Out) (In) Fluxgate Heading Sensor C-2000 Antenna Unit Remote Display FMD-811 External Alarm Buzzer OP03-136 Rectifier PR-62 10.2~31.2VDC 115/230VAC MODEL 841 MARK-2 CONFIGURATION

1 1.1 What is Radar? The term "RADAR" is an acronym mean-ing RAdio Detection And Ranging. Al-though the basic principles of radar weredeveloped during World War II, primarilyby scientists in Great Britain and the UnitedStates, the use of echoes as an aid to navi-gation is not a new developme...

2 Figure 1-1 How radar works A B C D Own ship(radar) D A B C Heading line Targets Own shipin center Range and bearingof a target, relativeto own ship, arereadable on the PPI. (A) Bird's eye view of situation (B) Radar picture of (A)

3 2. OPERATION 2.1 Control Description Cursor padShift cursor, VRMand EBL; selectitems and optionson menu. Selects display mode; erases heading error indication. Turns power on/off. Adjusts display brilliance. Sets radar in stand-by;transmits radar pulse. Selects radar range. Plots targets' trails. ...

4 0.5 Range Range ring interval Echo trail, AUTO tuningEcho trail elapsed time,echo trail time, tuning indicatorGuard zoneFast Time Constant(rain clutter suppressor)Echo stretchInterference rejector EBL Range ring Cursor Heading marker Guard zone area VRM HDG 326.8° SP Pulsewidth Heading (requireshe...

5 2.4 Transmitting After the power is turned on and the mag-netron has warmed up, ST-BY (Stand-By)appears at the screen center. This means theradar is now fully operational. In stand-bythe radar is available for use at anytime—but no radar waves are being transmitted. Press the [ST-BY TX] key to tra...

6 2.8 Adjusting GAIN, STC, A/CRAIN and FTC General procedure The [ECHO] key enables adjustment of thegain, STC, A/C RAIN and FTC. 1) Press the [ECHO] key. The following dis- play appears. AUTO 1 2 3 MAN AUTO 1 2 3 MAN GAIN STC ◆ ◆ [[ A/C RAIN 00 FTC 0 1 2 12 ECHO KEYTO EXIT Currentlevel Item selecte...

7 How to adjust A/C RAIN and FTC(suppressing rain clutter) The vertical beamwidth of the scanner is de-signed to see surface targets even when theship is rolling. However, by this design theunit will also detect rain clutter (rain, snow,hail, etc.) in the same manner as normal tar-gets. Figure 2-6 s...

8 1.5 NM 0.5 VRM range VRM Target VRM EBL + CURSOR 0.675 NM 220.9° R 0.675 NM 308.7° R Figure 2-8 Measuring range by the VRM 2.11 Measuring the Bearing There are two ways to measure the bearingto a target: by the cursor, and by the EBL(Electronic Bearing Line). By cursor Operate the cursor pad to bi...

9 To erase the EBL, press and hold down the[EBL] key for about three seconds. 1.5 NM 0.5 EBL Target EBLbearing VRM EBL + CURSOR 0.675 NM 300.1° R 0.675 NM 300.1° R Figure 2-9 Measuring bearing by the EBL Tips for measuring the bearing • Bearing measurements of smaller targets are more accurate; the ...

10 Table 1-1 Menu description Menu Function 1. Selects control panel backlighting; four is maximum backlighting.2. Selects brilliance for echo trails and markers; four is maximum brilliance. 1. Selects pulselength for 1.5 and 3 mile ranges.2. Selects radar interference rejector level; 3 provides hig...

11 2.13 Selecting the DisplayMode The display mode may be selected with the[DISP MODE] key. Four modes are avail-able (with navigation input): Normal, Nor-mal + Window, Normal + Nav Data, andNormal + Window + Nav Data. Each time the key is pressed the displaymode changes in one of the sequences show...

12 2.14 The Window Display The window display appears at the bottomright (or left) 1/4 of the display. Two typesof window displays are available: zoom andwide. Zoom doubles the size of the area se-lected by the operator, and wide (range-up)compresses and displays the entire radar pic-ture on the nex...

13 WPT-UP (waypoint-up) An azimuth stabilized display in which theline connecting the center with the top ofthe display indicates the bearing to the “TO”waypoint, which is selected on the naviga-tional equipment connected to the radar.When navigating a route and own ship en-ters the arrival zone of ...

14 pressing the [GUARD] key. When this isdone, G (ACKN) replaces G (IN) (or G(OUT)). Press the [GUARD] key again to reactivatethe alarm. G (IN) (or G (OUT)) replaces G(ACKN). Canceling the guard zone Press and hold down the [GUARD] key untilthe guard zone disappears. Notes on the guard alarm • When ...

15 corner on the display when the interferencerejection circuit is turned on. 2.18 Suppressing NoiseInterference Noise interference appears on the screen asmany bright dots. These dots can be sup-pressed by turning on the noise rejector. Notehowever that there are some forms of noiseinterference whi...

16 2.21 Echo Trails You can show the trails of targets in after-glow. This function is useful for alerting youto possible collision situations. Starting echo trail Press the [TRAIL] key to start the echo trailfunction. Afterglow starts extending fromtargets and "TRAIL" and the echo trail tim...

17 1.5 NM 0.5 HDG 326.8° 66° 04. 00N 166° 04. 00E VRM EBL + CURSOR 0.675 NM 240.1° R 0.646 NM 308.7° R DEPTH XTE SPD 350.0m 0.05NML 30.0KT WAYPOINT POSI L/L 12.0 NM 45.0° M AUTO Figure 2-18 Sample nav data display Setting up the nav data display 1) Press the [MENU] key. 2) Select Nav Data and press ...

18 4) ON or OFF. 5) Press the [ENT] key followed by the [MENU] key. ES appears at the top rightside on the display when the echo stretchfeature is on. Note 1: This function magnifies not only tar-gets but also sea clutter and radar interference.For this reason be sure the controls for adjust-ment of...

19 Canceling watchman Press any key while the radar is transmit-ting. (Pressing a key during stand-by causesthe radar to go to warm-up condition.) 2.27 Erasing the HeadingMarker The heading marker continuously appearson the display and shows your vessel’s head-ing. When this mark obscures a target e...

20 2.30 Outputting CursorPosition to Navigator Cursor position (NMEA0183 data sentenceTLL) can be output to the navigator con-nected to this radar by pressing and holdingdown the [HM OFF] key. 2.31 Displaying CursorPosition, Range and Bearing toCursor The cursor data indication at the bottom ofthe d...

21 Radar horizon Radar is essentially a “line-of-sight” phe-nomenon. That means you have just aboutthe same range to horizon with a radar asyou do with your own eyes. However undernormal atmospheric conditions, the radarhorizon is 6% greater than the optical hori-zon. Therefore, if the target does n...

22 On the other hand, hulls made from woodor fiberglass return much weaker echoes. Vertical surfaces, such as a cliff, are goodtargets provided they face the radar. Con-versely, horizontal and smooth surfaces suchas mudbanks, sandy beaches, and gentlysloping hills make poor targets because theydispe...

23 Indirect echoes Indirect echoes may be returned from eithera passing ship or returned from a reflectingsurface on your own ship, for example, astack. In both cases, the echo will return froma legitimate contact to the antenna by thesame indirect path. The echo will appear onthe same bearing of th...

24 Blind and shadow sectors Funnels, stacks, masts, or derricks in the pathof antenna may reduce the intensity of theradar beam. If the angle subtended at thescanner is more than a few degrees a blindsector may be produced. Within the blindsector small targets at close range may notbe detected while...

25 This chapter tells you how to keep your ra-dar in good working order. Before review-ing this chapter please read the safetyinformation which follows. 4.1 Safety Information ELECTRICAL SHOCK HAZARD T h i s e q u i p m e n tuses high voltageelectricity whichcan shock, burn orc a u s e d e a t h .Wh...

26 4.2 Preventative Maintenance Regular maintenance is important for goodperformance. Always keep the equipment asfree as possible from dirt, dust, and watersplashes. Make sure all screws securing thecomponents are properly tightened. A maintenance program should be estab-lished and should at least ...

27 4.4 Troubleshooting Table 4-2 contains simple troubleshootingprocedures which you can follow to try torestore normal operation. If you cannot re-store normal operation, do not attempt tocheck inside any unit of the radar system.Any repair work is best left to a qualifiedtechnician. Table 4-2 Trou...

29 ¡ The compass safe distance should be ob-served to prevent deviation of the magneticcompass. s s a p m o c d r a d n a t S s s a p m o c g n i r e e t S m 9 . 0 m 7 . 0 ¡ Do not paint the radome to ensure properemission of the radar waves. ¡ When this radar is to be installed on largervessels, co...

30 Mounting platform Holes for antenna unit: The mounting surface must be parallel withthe waterline and provided with five holeswhose dimensions are shown in the outlinedrawing attached at the end of this manual. The unit is adjusted so a target echo returnedfrom the bow direction will be shown on ...

31 7. Pass the cable through the hole at the bot- tom of the radome base. 8. Secure the cable with the cable clamping plate and gasket. Ground the shield and vi-nyl wire by one of the screws of the cableclamping plate. 9. Connect the wire to the RF unit. to one of the screws of the cable clamping pl...

32 • Make sure you allow enough clearance both to get to the connectors behind the unitand to allow you to get your hands in onboth sides to loosen or tighten the mount-ing knobs. Make sure you leave at least afoot or so of “service loop” of cables be-hind the unit so it can be pulled forwardfor ser...

33 Connections Connect the signal and power cables, theground wire and optional equipment as shownin Figure 5-12. RP HDG NMEA DJ-1 OPTION MARINE RADAR TYPESER.NO.DATECOMPASS SAFE DISTANCESTD M STEER M EQUPMENT CLASSFURUNO ELECTRIC CO., LTD 10.2-31.2VDC 3 GND 1 2 Signal cable connector Connect signal...

34 Navigation aid, video sounderconnection If your navigation aid can output data inNMEA 0183 data format, your vessel’s posi-tion in latitude and longitude, the range andbearing to waypoint, speed, and course maybe input to this radar, and be seen in the bot-tom text area. Further, if your video so...

35 J55 (NMEA) SPU9180 TLL, RSD J61 Navaid Echosounder Video plotter MODEL 841 M2 The position data from navaid can be used for the echosounder if a video plotter is not connected. Procedure 1. Unfasten the nuts fixing the waterproof con- nector to remove the covers of the power anddisplay unit. 2. R...

36 5.4 Initial Adjustment of Picture Follow the procedure below to obtain properradar picture. 1) Press the [POWER] key on the display unit. The display should light. Wait until the mes-sage “ST-BY” appears on the screen. (About1:30. 2) Press [TX ST-BY] key to transmit. The ra- dar will start transm...

37 5.6 Entering Initial Settings 1) At the Installation Setup 1 menu, press the cursor pad to select Key Beep. (Key Beepturns on or off the buzzer which sounds whena key is pressed.) 2) Press the cursor pad to select OFF or ON. 3) Select Hdg Sensor. 4) Select type of heading sensor connected to t h ...