Pcf (Position Correction Factor) - Lowrance GlobalMap 2000 Installation And Operation Instructions Manual

PCF (Position Correction Factor)

Another method used to reduce the error factor between datum is called
PCF, or Position Correction Factor. This unit gives you the capability to
move or "offset" the position shown on the display to match the one on the
chart. The unit will add this offset or PCF to all position displays 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 cancel
the error. In general terms this feature should only be used if your map
indicates what the possible error is. This feature should always be reset to
zero (0) when finished with that 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 .010
degrees less than the one on the chart. Using the Position Correction
Factor (PCF) Offset feature, you make the unit read the same as the chart.
If you move, the unit will continuously add the change to all position
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. This
offset is saved in memory. It doesn't change when the unit is turned off.
However, a Preset does erase the PCF factor.
To set the PCF factor, first press
the MENU key three times, then
press the key next to the "Da-
tum Translations" label. Finally,
press the key next to the "PCF"
label at the bottom of the dis-
play. The screen shown at
right appears.
Now enter the correction for
your location. 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
have entered 0 degrees, .012 minutes north latitude and 0 degrees, .068
minutes east longitude as the PCF offset. That is the difference between
the present position shown on the unit and our position shown by the chart.
In other words, our position shown on the unit is 0.012 minutes south and
0.068 minutes west of the position shown on the chart.
After you've entered the desired offset, press the key next to the "PCF
Mode ON OFF" label. This turns the PCF correction factor that you entered
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