Northrop Grumman Sperry Marine VisionMaster FT, Руководство пользователя

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Annex A - SARTs, Beacons & Target Enhancer Radar/Chart Radar User Guide
Detection on X-Band Radar
A-2 65900010
When the range to the SART is reduced to about 1 NM, the radar display
may also show the 12 responses generated during the fast sweeps. These
additional dot responses, which are also equally spaced by 0.64 NM, will
be interspersed with the original line of 12 dots. They will appear slightly
weaker and smaller than the original dots.
Radar Range Scale
When looking for a SART, it is preferable to use either the 6 or 12 NM
range scale, see Range Scales. This is because the total displayed length
of the SART response of 12 (or 24) dots may extend approximately 9.5nm
beyond the position of the SART and it is necessary to see a number of
response dots to distinguish the SART from other responses.
SART Range Errors
When responses from only 12 low frequency sweeps are visible (when the
SART is at a range greater than about 1 NM), the position at which the first
dot is displayed may be as much as 0.64 NM beyond the true position of
the SART. When the range closes so that the fast sweep responses are
seen also, the first of these dots will be no more than 150 meters beyond
the true position.