Simrad ARGUS FMCW 3G, User Manual

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Radar presentation and video processing | Argus Radar Operator Manual
The row under PPI area
7 6 5 4 3 2 1
Under the PPI area there is the row for the presentation modes, in which the following con-
trols are located (note that widgets can be shown from left to right or viceversa, depending
on the currently used layout):
1.
Range Scale Increase/Decrease
2.
Range Rings ON/OFF
3.
PPI Centre/Off Centre
4.
P Reset/TM Reset
5.
Sea Stab/Gnd Stab
6.
Heading Line On/Off
7.
Tune
Range scale increase/decrease
The function of the two square buttons labelled with big “-“ (minus) and “+” (plus) is to de-
crease or increase the range scale by one step. Between them, a label is indicating the actual
range scale value in NM. There is a direct link between range scales and transceiver PRF. Each
time the range scale is changed, the optimal PRF is selected according to the following table:
Range scale (NM) Pulse length (µs) PRF (Hz)
0.125 0.07 3000
0.25 0.07 3000
0.50 0.07 3000
0.75 0.07 3000
1.5 0.07 3000
3 0.07 3000
6 0.25 1500
12 0.25 1500
24 0.80 750
48 0.80 750
96 0.80 750
The PRF is controlled by the range scale setting of the master unit only.
Range rings on/off
Pressing the “Range Rings On/Off” button, the range rings will be enabled/disabled on the PPI.
With the range rings, the operator can approximately determine the distance to a target . The
rings are equally spaced and the distance between the rings is written on the above men-
tioned button.
With reference to the bearing scale, the operator can approximately determine the bearing
of the target from own ship position if the presentation is Head Up, and from the north if the
presentation is North Up.
PPI Centre/Off centre
Next to the Range Rings button there is the PPI Centre/Offcentre label. The radar picture is
normally shown with own ship at the centre of the display and in this case the label indicates
“PPI Centre”. However, the operator can move the centre, so that the ship is offset by up to