Clipper ECHO SOUNDER, Manual

13

CHANGING THE KEEL OFFSET

(Enable engineering mode, see page 11)

The keel offset represents the distance between the transducer itself
and the bottom of the keel. When a keel offset is stored, all
measurements (including alarms) are shown as if measured from the
bottom of the keel instead of the transducer. If, for example, the bottom
of the keel is 0.4metres below the depth of the transducer in the hull,
setting the offset to 0.4m will ensure that the readings displayed show
the depth below the keel instead of from the transducer.

The DEEP and SHALL buttons are used separately to adjust the
keel offset value in the range 0 to 2.5m (8.3ft.), In steps of 0.1m
(0.5ft.). No repeat is embodied on the keys because of the small
range of adjustment. Pressing DEEP increases the keel offset
depth, and pressing SHALL reduces the keel offset depth.
Press the ILLUM key to return to normal echo sounding mode.

CHANGING BETWEEN KEEL AND SURFACE OFFSET

(Enable engineering mode, see page 11)

It is sometimes preferable to measure the depth from the surface
instead of the transducer or keel. If, for example, the transducer is
0.3m below the surface, setting a surface offset of 0.3m will ensure
that the readings displayed show the depth below the surface
instead of from the transducer itself. Pressing the ENTER and
DEEP buttons together switches between the keel depth and
surface depth measurement modes, as shown on Figure 9.

ENTER

SHALL

DEEP

ILLUM

METRES

ENTER

SHALL

DEEP

ILLUM

METRES

Figure 9 - Switching Between Surface and Keel Depth.