Default Ant Hieght, Near/Mid/Far Stc Curve - Furuno FAR-2107 Series Service Manual

4.4.3 DEFAULT ANT HIEGHT, NEAR/MID/FAR STC CURVE

INITIALIZE -> 2: ECHO -> 6, 7, 8, 9
Parameters determining the STC curve are listed below.
Item
MODEL
STC RANGE
SEA CONDITION
ANT HIEGHT >
DEFAULT ANT
HIEGHT
NEAR STC CURVE
MID STC CURVE
FAR STC CURVE
Set the antenna height for the setting of DEFAULT ANT HIEGHT, by "[PICTURE] ->
9 -> 3: ANT HIEGHT". The STC curve is primary set by ANT HIEGHT.
The STC control is executed by the IF board of the TR unit.
Range
Near STC Curve
(2/2.5/3/3.5)
By adjusting the [A/C SEA] knob, the STC curve moves up and down. The ANT
HIEGHT, SEA CONDITION and pulse length determine turning points of the curve.
And the setting of the STC RANGE changes the turning points of MID STC and FAR
STC. The higher is the antenna and the worse is the sea condition, the more the control
distance of (1<5) STC is extended.
For instance, if the antenna height is 30 m for the X-band radar, the NEAR turning point
is 4 to 5 NM and the MID turning point is 19 to 20 NM. In AUTO STC, the optimum
STC curve and movement of STC curve (upward and downward) are automatically
controlled according to a reception signal level and Range.
Table 4.4.1 Setting Values Related to STC Curve
INITIALIZE->4->6
[PICTURE]->9->4
[PICTURE]->9->2
[PICTURE]->9->3,
INITIALAIZE->2->6
INITIALIZE->2->7
INITIALIZE->2->8
INITIALIZE->2->9
[A/C SEA] VR ADJ
Far STC Curve
(6/7/8)
MID STC Curve
(3/4/5/6)
STC RANGE
(+10)
Fig 4.4.1 STC Curve
4-15
Setting Parameter
X band: 6/12/25UP/25DOWN
S band: 50/30UP/30DOWN/60
-10 - +10
1/2/3/4/5
5/7.5/10/15/20/25/30/35/
40/45/more 50m
2/2.5/3/3.5
3/4/5/6
Note
6/7/8
Limit: 24NM
[GAIN] VR ADJ
The STC effective range is
restricted up to 24 NM by the RFC
board. The larger is the gradient
coefficient of the STC curve, the
larger are the changes
in attenuation.
Initialize Setting Initialize Setting
Initialize Setting Initialize Setting
4.4
Default Remarks
At
X band
installation
+ 0
Depends
on
Picture
At
15
installation
3
4
7