Furuno 1830 - Range Selection

The solid radial line at 0° is the heading mark.
on the screen and indicates the ship's heading.
the mark by holding down the touchpad.
The heading mark is always
You may temporarily erase
The nearly invisible line rotating radiaily aroand the screen is called the
"sweep." The aweep rotates synchronously with the scanner, so at any
given ttme the direotion in whioh tho scanner is pointing is knowii. With
every rotation echoes appear on the sweep as brighter spots of fight, thus
preaenting a complete pie ture of the surroundlng area.
i'lacing the radar in standby helps extend component life. Therefore, when
the radar wiU not be used for an extended period of time, but you want to
keep it in a State of readiness, set it to "ST-BY" mode by pressine the
touchpad again. L^J
j^nge Selection
The range selected automatically determines the fix ed range ring interval,
the nuiiiUei- of fix ed range rings, pulselength. and pulse repetition, for
optimal detection in both short and long ranges (see the table below). Most
ranges are either half or twice their neighbor for easy identification of
targets when changing the range. The present range emd ita ring interval
are displayed at the top left corner of the CRT.
The range chosen varies depending on circumstances. When navigating in
or around crowded harbors, it is best to select a range between 0.5 and
1.5nm to watch for possible collision situations. If you select a lower range
while on open water, inerease the range occasionally to watch for veaaels
that may be heading your way. Rcmember that the maximum range a radar
can see is dependent on many factors. Factors affeeting maximum range are
discussed in the Application section.
There are eight ranges available: 0 .25 . 0.5, 0 .75, 1.5, 3, 6, 12 and 24nin.
To select a range, press the (^2 o*" touchpad. depending on whether
you want to select a higher range or a lower range. It is possible to
inerement or decrement the range aetUng autoiuaUcally by holding down the
( $+] or touchpad.
Table 2 Range Setting and Corresponding Fixed Range Ring Interval
and Number of Fixed Range Rings
Range (nm)
0.25
0.5
0.75
1.5
3
6
12
24
Range Ring
Interval (nm)
0.05
0.1
0.25
0.25 0.5
1
2
4
No. of Fixed
Range Ri ners
5
5
3
_
6
6
6
6
8
27