JRC JLN-900 - Page 139

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x S3 GEO BOW = enter the distance from the transducer to the bow in meters
x S4 GEO STERN = enter the distance from the transducer to the stern in meters
If there is no rot-gyro input to the Sig. Distributor, then force gyro input to zero by entering the
following:
x S2 DL GYRO INPUT = ANALOGUE
o S2.1 DL GYRO INPUT = 0
x S3 GEO BOW = 1
x S4 GEO STERN = 1
In this case, the transverse speed window on the SD4-2 Main Display will indicate the
transverse speed at the transducer location.
Ne
g
ative Transverse s
p
eed
Positive Longitudinal speed
GEO BOW
GEO STERN
Transducer location
SD4
Vessel’s center of rotation and rotational direction
SD4 INVERTED
SD4 reference
frame
Forward
Port
SD4 INVERTED
reference frame
Forward
Port
Figure 1. Example of SD4 INVERTED. The transducer senses positive longitudinal and negative transverse
speed and the vessel rotates counter clockwise, as indicated by filled arrows. The indicators will display
according to their different reference frames:
x The SD4 will display forward and port speed.
x The SD4 INVERTED will dis
p
la
y
backward and
p
ort s
p
eed.