Icom MR-1000RTM, MR-1000TTM, EX-2714 Basic Radar Theory, Side-lobe echoes, Indirect echoes

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BASIC RADAR THEORY 8

Radar uses a form of electromagnetic radiation, which like light, can be reﬂected. Because of this property, some objects may cause false echoes on the screen where in fact no targets actually exist.

These echoes may appear if a large vessel, bridge, or tank is in proximity. Operators should be familiar with the ef- fects of these phenomena. In some cases, echoes can be reduced.

■Side-lobe echoes

Radiation can escape on each side of the beam inside the lobes. If a target reﬂects this radiation, it will be dis- played on the screen as an echo.

Main beam

Side lobes

Side-lobe echoes usually occur at short ranges and as a result of large (strongly reﬂective) targets. They can

be reduced	with proper	adjustment of the
[SEA]/[	] control.
See p. 10 for the [SEA]/[		] control.

True echo

False echoes

■Indirect echoes

Indirect echoes may be returned from either a passing ship, or returned from a reﬂecting surface, such as a mast on your own ship.

Target

Scanner

Mast or similar obstruction

Target

Own ship

An indirect echo from a reﬂecting surface will appear on a different bearing from the direct (true) echo, but the distance will be approximately the same for both.

True echo

False echo

True echo

Bridge

Indirect echo

An echo is reflected at this point.

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Contents MR-1000R EX-2714Radome type unit Qty System cable OPC-1188 15 m Model Name CRT Display Scanner UnitEX-2780Open array type unit Qty SX-2713/277910 inch CRT display unitWord Definition Rine RadarTable of Contents Radiation Hazard Front panel Panel Description@0DISPLAY Brilliance Switch Brill 9EBL1 VRM1 Switch EBL1 VRM10PARALLEL Index Line Function PI 2HEADING Line OFF Function HL OFFScreen @9MODE Indicator$3HEADING Indicator #9CURSOR Indicator$8OWN Ship Vector Indicator 6TIME Indicator %7TIME IndicatorMenu ATA Automatic Tracking Aid Turning power ON/OFF Checking the installationChecklist Basic OperationBasic operation SEA function Rain functionOFF Center function Stretch function IR functionZoom function Zoom function expands the target to two times normal sizeTrails function Power save functionShip speed indication Bearing settingPosition indication Waypoint indicationUsing the variable range marker Using the ﬁxed ringsDistance and Direction Measurements Distance measurementBearing and Distance measurement Using the EBL and VRMDistance and Direction Measurements Push EBL1 VRM1/ to clear EBL1 and VRM1Measuring the distance and direction between 2 targets Advanced measurementsPush EBL2 VRM2/ to display the EBL2 and VRM2 Push Ù Ú Ω ≈ to move the cursor on the other targetAlarm zone setting Alarm FunctionZone alarm setting Setting and using the alarm functionATA Automatic Tracking Aid ATA menu settingPlotting marks Course and speed vector ATA operationATA Automatic Tracking Aid ATA PlotsSide-lobe echoes Basic Radar TheoryIndirect echoes Minimum range Multiple echoesBasic Radar Theory Distance resolution Target resolutionDirection resolution Blind and Shadow sectorsConnecting the units Installation and ConnectionsPower source requirement Ground connectionInstalling the display unit Ship’s bow direction Mounting the EX-2714 scanner unitScanner unit disassembly Wiring the EX-2714 system cableConnect the system cable Mounting the EX-2780 scanner unit Wiring the EX-2780 system cable Beacon Fixing the EX-2780 scanner unitOther Functions All resetAntenna rotation speed Test pattern indicationService man menu Service MAN MenuSelect the language HDG adjustment Timing adjustmentService MAN Menu Range selection SPD adjustmentError message list Error MessageMessage Condition Periodic maintenance MaintenanceScanner unit maintenance Display unit maintenanceEX-2714 Radome SpecificationsEX-2780 Open array Display unit SpecificationsBearing Speed Position External Data ListSX-2713/2779 Display mounting bracket template EX-2714 Radome template EX-2780 Open array type template