Garmin 135 GPS Receiver User Manual


 
Water Type - Maximizes the sounder’s operation in cold, cool, or warm water and
salt or freshwater. Has one field for water temperature and one for water composi-
tion. Set the water temperature option to ‘Cold’ if the water is below 40ºF, ‘Cool’ if
it is between 40º- 80ºF, and ‘Warm’ if it is above 80ºF. Set the water composition
field to salt or freshwater depending on where you are fishing.
To select water temperature or composition:
1. Use the
R
keypad to select either the temperature or water composition field and
press
T
. A corresponding submenu will appear.
2. Highlight your submenu selection and press
T
.
Noise Rejection - Removes cross talk from other sounders or ignition noise due to
poor boat motor installation (non-shielded plugs, etc.). The ‘AUTO’ setting is the
default and identifies the presence of crosstalk noise, and turns rejection on when it
needs to. When the noise disappears, it turns the rejection off. The ‘OFF’ setting pre-
vents the unit from removing any perceived noise from the display. The ‘ON’ setting
removes anything the unit thinks is cross talk noise and attempts to “repair” the dam-
age done by suspected interference with real echoes.
To set noise rejection:
1. Highlight the “Noise Rejection” field and press
T
. A submenu will appear.
2. Select from OFF, AUTO, or ON and press
T
.
Keel Offset - allows you to set the point from which the GPSMAP 135 Sounder will
measure depth. This makes it possible to measure depth from the bottom of your keel
instead of from the transducer's location. A positive number will measure depth from
a deeper point while a negative number reflects a shallower point.
To set keel offset:
1. Highlight the “Keel Offset” field and press
T
. Use the
R
to enter the keel
offset value and press
T
.
A. The correct temperature setting will ensure that
the sounder gives more accurate depth
measurements.
B. Use the noise rejection feature to minimize
interference from nearby electronics.
33
A
B
SECTION
3
SOUNDER PAGE
Sounder Setup
GPS 135 Rev C 8/4/98 4:18 PM Page 33