Vexilar LC-507 - Manual (Page 22)

22
SEEING FISH
Although the LC-507 does not use any type of fish identification
symbols on the display, it can be very easy to spot fish. Fish pass-
ing through the 107 kHz cone will appear as an arc, or partial arc.
Fish on the 400 kHz
beam can also be dis-
played as arcs, but will
most likely, appear more
like irregular blocks.
Here is how it works.
The 107 kHz beam has a
lot of power and a very
wide cone angle. When
the fish appears at the
edge of the cone it is far
away from the transducer. The display begins to draw the target on
the screen. As the fish gets closer to the center of the cone the target
appears to get shallower, or closer, and the unit draws the target line
getting shallower. When the fish passes to the other side of the cone
it appears to get deeper, or farther away. The unit now draws the
line going deeper, until it is no longer visible. The result is an arc
drawn on the display. If the fish passes on the edge of the cone you
will only see a partial arc. The principal is the same for the other
beam, but because of the smaller cone angle, full arcs are much less
likely to be seen. Fish within this beam will be much closer to you
than they may be with the wider 107 kHz beam. They ,also, are more
likely to be further away from the bottom. This is due to the “Dead
Zone” effect of the wider cone.
The Clean Line feature, when set to the proper level, can also
help you identify fish from floating debris. If the target appears
cleaned out, you can assume it's something significant, like a fish.
In heavy weeds this can be more difficult to see.
Figure 26