How To Show Sart Marks On The Radar Display; General Remarks On Receiving Sarts - Furuno FAR-2218 Operator's Manual

2. RADAR OBSERVATION
2.3.2

How to show SART marks on the radar display

This radar is equipped with a feature that optimally sets up the radar for SART detec-
tion. This feature automatically detunes the radar receiver out of its best tuning condi-
tion. This erases or weakens all normal radar echoes, but the SART marks are not
erased because the SART response signal scans over all frequencies in the 9 GHz
band. When the radar approaches the SART in operation, the SART marks will en-
large to large arcs, blurring a large part of the screen.
1. Open the menu.
2. Select [1 ECHO].
3. Select [7 SART].
4. Select [ON] to show SART marks on the radar display, or select [OFF] to hide
SART marks.
When the SART function is active, the settings listed in the table on the following
page are automatically made to radar functions:
Range
Pulselength
Echo Stretch
Noise Rejector
Echo Averaging
Interference Rejector
Performance Monitor
A/C RAIN
5. Close the menu.
The indication "SART" appears at the top of the screen, in yellow text, when this fea-
ture is active. Be sure to turn this feature off when SART detection is no longer your
objective.
2.3.3

General remarks on receiving SARTs

SART range errors
When responses from only the 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
can 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 will be no
more than 150 meters beyond the true position.
Radar bandwidth
This is normally matched to the radar pulselength and is usually switched with the
range scale and the associated pulselength. Narrow bandwidths 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 5 MHz will attenuate the SART signal slightly, so it is
preferable to use a medium bandwidth to ensure optimum detection of the SART.
2-6
Setting Changed to
12 NM
Long
Off
Off
Off
Off
Off
Off