Raytheon NSC 18, Руководство пользователя

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Operator Manual
Raytheon Marine GmbH
Germany
R
NSC 18
RADAR
2 − 29
3748DOC020102 Edition: 14.JAN.2005
2.3.1.5 RAIN RATE
Step 1
Select MANual mode
Step 2
The function of the RAIN control is to enable the operator to suppress radar
returns which are the result of radar signals reflected from rain drops.
This effect is commonly known as rain clutter. As with sea clutter, the rain clutter
tends to mask small targets (or large targets if the rain is intense).
When heavy rain is falling in the vicinity of the operator’s ship (up to 6 − 10 nm)
and the resulting rain clutter is obscuring nearby targets, then the rain rate slider
should be used. Advance the rain rate control slightly and observe the results
(wait 3 scans).
The ultimate goal is to reduce the nearby rain clutter until it is a very light speckle
at the dim level. This setting will reduce the rain returns and will have little effect
on strong constant target video returns. Weaker targets (usually appear where
rain returns are less intense) may be suppressed along with the rain.
Most of these weaker targets can be restored by making an FTC adjustment
(see chapter 2.3.1.6).