GPS Coordinate Question

[sparetime]

I have a question regarding an old Garmin EMap GPS that I have. It accepts coordinates in the 00deg00min.000 format. My owners manual doesn’t tell me the method to convert from 00deg00min00sec.00 format.

I realize everything is based on 60. For example

48deg25min48sec.79N

92deg47min48sec.37W

Is that

48deg25min.8 or

48deg25min.487

Just not use to the entry format on the old GPS system. I have had it in a drawer for years and decided to give it a try before purchasing a more modern unit.

[bobbymalone]

google: GPS Latitude and Longitude Converter

top hit

also, if this is important to you I might delete those coords

[McGurk]

To convert from Degree Minute Second (DMS) to Degree Minute (DM) you need to only convert the seconds into hundredths of a minute. To do that, take the seconds unit, and divide that number by 60. You now have a new number that follows a decimal point, which you can apply after your minutes unit, as it is now a portion of a minute.

Example: Degrees Minutes Seconds Dd M' S": 10d 20' 30.0" (30.0" = 30 seconds = 1/2 minute)

30" / 60 = .500

.500 now goes after 20' to become 20.500'

Your new number is 10d 20.500'

If you want to convert that into Degree Decimal (DD), you can take the next step. Take your new answer from the seconds conversion, and divide that by 60. Your new number will also follow a decimal point, and can be added after your degree number.

(from above) 10d 20' 30" = 10d 20.500'

20.500 / 60 = .34167

.34167 goes after 10d to become 10.34167d

Careful with your rounding, and don't imply mathematical precision. Just because a calculated answer goes 8 places beyond your decimal, you need to round off at the level of precision of your original info.

To go backwards, you need only drop the whole number, multiple the decimal portion you are trying to convert by 60, and use the new number as needed. Repeat as necessary by dropping the new whole number and multiplying the decmal portion by 60.

10.34167, only take the decimal portion of .34167

.34167 * 60 = 20.500 for DM

10d 20.500'

.500 * 60 = 30.0 for DMS

10d 20' 30.0"

[Macgyver55]

Otherwise, You should also be able to go into the setup menu, go to the "Advanced" tab and change the "Location Format" to which ever format you want it to read.

[Pooh]

i can change it on my ETrex u should be able to also on a Emap