Northrop Grumman Sperry Marine VisionMaster FT, User Manual

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Radar/Chart Radar User Guide Annex A - SARTs, Beacons & Target Enhancer
Detection on X-Band Radar
65900010 A-3
Radar Bandwidth
This is normally matched to the radar pulse length and is usually switched
with the range scale and the associated pulse length. Narrow bandwidth of
3-5 MHz are used with long pulses on long range scales and wide
bandwidths of 10-25 MHz with short pulses on short ranges.
A radar bandwidth of less than 5MHz will attenuate the SART signal
slightly, so it is preferable to use a medium bandwidth to ensure optimum
detection of the SART, see Radar Transmission Pulse Length.
Radar Side Lobes
As the SART is approached, side lobes from the radar antenna may show
the SART responses as a series of arcs or concentric rings. These can be
removed by the use of the anti-clutter sea control although it may be
operationally useful to observe the side lobes as they may be easier to
detect in clutter conditions and also they will confirm that the SART is near
to own ship.
Detuning the Radar
To increase the visibility of the SART in clutter
conditions, the radar may be manually detuned
to reduce the clutter without reducing the SART
response. For information on manual tuning adjustment see Radar, Radar
Fine Tuning.
CAUTION:
Care should be taken in operating the radar in a detuned
condition as other wanted navigational and anti-collision
information may be removed. The tuning should be returned to
normal operation as soon as possible.