Garmin 182 Manuale Proprietario

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Appendix A
Loran TD
Loran TD System
LORAN C is a radio navigation aid operated and maintained in the United States by the United 
States Coast Guard. The name LORAN is an acronym for “LOng RAnge Navigation”. The LORAN 
system covers the entire United States and the U.S. Coastal Confluence Zone. From the perspective 
of a mariner, the system is used for ocean and coastal navigation. It can be used as a supplemental 
system for harbor and harbor approach navigation, and it is used for inland navigation by recreational 
vehicles. 
LORAN TD Feature
The LORAN TD (Time Delay) feature eases the transition from using LORAN to using GPS. The 
GPSMAP unit automatically converts GPS coordinates to LORAN TDs for those who have a collection 
of LORAN fixes for favorite fishing spots and other waypoints recorded as TDs. You can display your 
position as a TD or enter waypoints as TDs. The accuracy to be expected from this conversion is 
approximately thirty meters. When the unit is placed in the LORAN TD format mode, it simulates 
the operation of a LORAN receiver. Position coordinates may be displayed as TDs, and all navigation 
functions may be used as if the unit was actually receiving LORAN signals.
Using the LORAN TD Format
When creating new waypoints using LORAN TD coordinates, you must set the correct LORAN 
chain number and secondary stations in the Setup TD field before storing the waypoint. You must have 
the correct chain number as well as the secondary station identifiers to use this option correctly. These 
values will vary per coordinate set or geographical location. Failure to enter correct information could 
result in inaccuracies for the desired destionation. After the waypoint is stored in unit memory, it will 
always reference the LORAN chain number and secondary stations currently selected in the Setup TD 
field. If you enter a different LORAN chain number, change the secondary stations or offsets in the 
Setup TD field, the active waypoint information will reflect those changes. Since the GPSMAP unit does 
not rely on the LORAN signal for navigation, it can reference a different GRI chain and/or secondary 
stations and still navigate to the location stored in memory.
You may change to Loran TD from the Units 
Tab on the Main Menu.