Converting Waypoints From Datum Nad27

[+amytincan]

I have waypoints from a book...listed as coordinates compiled using All Topo Maps (iGage) software (Datum=NAD27)

 

Latitude listed (degrees/minutes/seconds) and UTM coordinates.

 

all I want to do is check to see if caches are nearby, using geocaching.com

 

so how do I convert a waypoint from that datum?

[+The Leprechauns]

Sounds like you need to pay a visit to jeeep.com. Enjoy your trip!

[+wolf452]

ATC, if all you want are nearby caches you don't really need to convert. While 27 and 83 are different, they are still within the ballpark. I would use them for searching. You will need to convert min/sec to dec minutes.... divide the seconds by 60 to get decimal minutes 42d34m45s = 42d34.75m....

Edited October 29, 2004 by wolf452

[gm100guy]

Go to the setup of your gps and change the datum to nad 27.

 

Change the units to utm.

 

Enter the numbers for the waypoints.

 

Go back to your setup and change it back to the 84 datum.

 

Go to units and change the unit back to dd min sec and read the number it the gps will have done the conversion for you.

 

[+amytincan]

can this be done switched around from one to the other....if I want to use the UTM on the trail but the other way the rest of the time?

[gm100guy]

Most gps's let you have a screen with 2 postion formats showing. Primary and secondary.

 

[+NightPilot]

You can switch between datums at will. The GPS automatically changes the numbers to match the chosen datum. You need to always be in WGS84 for entering geocaching waypoints, but after they're entered, you can switch to any datum and the GPS will direct you to the waypoint. So if you want to use UTM while searching, just change the datum and follow the GPS.

Edited October 30, 2004 by NightPilot