Pcf - Lowrance GlobalNav 310 Installation And Operation Instructions Manual

PCF (Position Correction Factor)
Another method used to make your display match a chart or map is
called "PCF" or Position Correction Factor. This unit gives you the capa-
bility to move or offset the position shown on the display to match one on
the chart. The unit will add this offset to all position and navigation dis-
plays at all times.
Remember, the position error on any radio navigation system is very
dynamic and the PCF offset should never be used in an attempt to can-
cel the error.
In general terms, PCF should only be used if your map indicates what
the possible error is. PCF should always be reset to zero when you're
finished with the chart.
For example, suppose you are stopped at a location that is accurately
marked on a chart. Your unit shows a longitude position that is .244 min-
utes east of the one on the chart and .047 minutes north latitude. Using
the PCF feature, you can make the GlobalNav 310 match the chart you're
using. If you move, the unit will continuously add the change to all posi-
tion, navigation, and mapping displays. This makes it more closely match
the datum used by the chart. For this reason, you should be careful when
entering the PCF offset. It's saved in memory and doesn't change when
the unit is turned off. However, resetting
the unit does erase the PCF offset.
To change the PCF offset, first press the
MENU key, then highlight the "GPS
Setup" label and press the right arrow
key. Now highlight the "Set PCF Offset"
label. Finally, press the right arrow key
again. A screen similar to the one at right
appears.
Now enter the correction for your loca-
tion. Remember, this is the difference
between the location shown on the
present position display and the position
shown on the chart. In this example, we
entered 0 degrees, 0.047 minutes north
latitude and 0 degrees, 0.244 minutes
east longitude. That is the difference be-
tween the present position shown by the
GlobalNav 310 and the one on our chart.
45