Furuno FR-2125V Operator's Manual page 30

4. Press the [2] key to select RINGS BRILL.
5. Press the [2] key again. Each pressing gradually increases the brightness of the rings
in 4 steps and the fifth pressing erases them.
6. Press the [ENTER] key to confirm you selection.
7. Press the [RADAR MENU] key to close the menu.
1.17.2 Measuring the range with the VRM
Use the Variable Range Markers (VRMs) for more accurate measurement of the range to
a target. There are two VRMs, No. 1 and No. 2, which appear as dashed rings so that you
can discriminate them from the fixed range rings. The two VRMs can be distinguished
from each other by different lengths of dashes.
1. Press the [VRM ON] key to display either of the VRMs. Successive presses of the
[VRM ON] key toggle the active VRM between No. 1 and No. 2 and the currently active
VRM readout is marked with >.....<.
2. Turning the VRM control, align the active variable range marker with the inner edge of
the target of interest and read its distance at the lower-right corner of the screen. Each
VRM remains at the same geographical distance when you operate the RANGE+ or
RANGE- key. This means that the apparent radius of the VRM ring changes in propor-
tion to the selected range scale.
3. Press the [VRM OFF] key to key to erase each VRM.
340
330
No.1
320
VRM
310
300
290
280
270
260
250
240
230
220
210
200
Active VRM is identified
with this marker.
Figure 1-20 How to measure range with VRM
000
350 010
020
030
Target
040
blip
050
060
070
080
090
100
No.2
110
VRM
120
130
140
150
VRM
160
190
170
180
>0.66SM<
1.18SM
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