1. OPERATIONAL OVERVIEW
1-51
1.32
How to Measure Range
The range to a target can be measured three ways: with the fixed range rings, with the
cursor, or with the VRM.
Use the fixed range rings to get an estimate of the range to a target. The rings are the
concentric solid circles on the display. The number of rings is automatically set by the
current range scale. The distance between the rings is the range ring interval, and the
current interval appears at the upper-left position on the screen. To measure the range
to a target with the range rings, count the number of rings between the center of the
display and the target. Check the range ring interval and estimate the distance of the
echo from the inner edge of the nearest ring.
1.32.1
How to show/hide the range rings
1. Open the menu.
2. Select [3 NAV TOOLS] to show the [NAV TOOLS] menu.
3. Select [4 RANGE RINGS].
4. Select [ON] or [OFF] as appropriate.
5. Close the menu.
1.32.2
How to measure range with the variable range marker (VRM)
There are two VRMs, No. 1 and No. 2, which appear as dashed rings so that you can
distinguish them from the fixed range rings. The two VRMs can be distinguished from
each other by the different lengths of their dashes; the dashes on the No. 2 VRM are
longer.
There are two methods for measuring range with the VRMs, using the
VRM
key and
on-screen menu box operation.
000
010
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VRM1
VRM2
Target echo
Currently active VRM is highlighted.
Range to VRM
TTG to VRM
28.11
36.44
NM
VRM1
VRM2
TTG 50:00
60:00
TTG
NM
Summary of Contents for FAR-2218
Page 132: ...1 OPERATIONAL OVERVIEW 1 110 This page is intentionally left blank ...
Page 176: ...3 TARGET TRACKING TT 3 36 This page is intentionally left blank ...
Page 202: ...4 AIS OPERATION 4 26 This page is intentionally left blank ...
Page 232: ...5 VIDEO PLOTTER OPERATION 5 30 This page is intentionally left blank ...
Page 294: ......