Intel 150SX - Manual (Page 12)

the transducer, there is often enough
energy left in the signal to be reflected
off the surface of the water back to the
bottom a second time. Second returns
appear as a slightly weaker bottom
representation exactly twice the depth
of the primary bottom return. The
second return is most likely to occur in
shallow water and in areas of relatively
hard bottom.
Fish ID. The 150SX uses advanced
signal processing to further evaluate any
sonar return between the surface and
the bottom. For instance, a small school
of bait fish usually appears as a dense
cluster of individual dots. If the return meets certain additional criteria, a fish
symbol will be assigned. There are three different size fish symbols used to
indicate the intensity of the sonar return. While signal intensity is a good
indicator of relative fish size, different species of fish have different sonar
characteristics, so it is not always possible to distinguish fish size between
varying species. The signal intensity is "normalized" for depth so that a
small fish close to the boat does not appear as a large fish symbol.
ID+ adds an additional piece of information to help the user locate fish. On
selected fish symbols, the digital depth of the designated fish is drawn to
help locate the fish vertically.
CONTROL FUNCTIONS
The 150SX uses a simple five button keypad for all user input. Press any button
and an audible “chirp” confirms the control input. If a button has no function
or is inappropriate for the situation, an audible “error” is heard. The unit sounds
multiple chirps.
Power. The Power button powers the 150SX up for normal operation. When
the unit is on, POWER turns the unit off. POWER can also be used to go directly
into Simulator mode. To enter simulator, with the unit powered off, press and
hold POWER for several seconds until a continuous chirp is heard.
10
USING THE 150SX
CONTROL FUNCTIONS
Thermocline Second Return