GPS co-ordinates

[Rob Jones]

Not sure if this is a daft question but I was wondering if somebody could explain how to input GPS co-ordinates.

I have a Lowrance GPS - If I take a co-ordinate of 050 39 764 N the GPS will not accept the 764 part as it is set in Seconds (therefore only goes to 60) Is there a simple method of changing the 764 part into seconds or do I have to change the GPS config (of which I have tried and cant)

[Phil]

.6

[rads]

Originally Posted by Rob Jones

I have a Lowrance GPS - If I take a co-ordinate of 050 39 764 N the GPS will not accept the 764 part as it is set in Seconds (therefore only goes to 60) Is there a simple method of changing the 764 part into seconds or do I have to change the GPS config (of which I have tried and cant)

There are two systems of writing co-ordinates:
Degrees, Minutes, and Decimal Minutes
OR
Degrees, Minutes and Seconds.

Your 764 is the decimal minutes part of the co-ordinate, and means 0.764 of a minute eg whole co-ordinate is 50 degrees, 39.764 minutes.

Since there are 60 seconds in a minutes, 0.764 minutes = (0.764*60) 45.84 seconds, so to the neares second, the co-ordinat is 50degrees, 39 minutes, 46 seconds.

Basically multiply the last part of the co-ordinat by 60 to convert decimal degrees into seconds.

Having said that, we enter decimal degrees into our Lowrance.....

[Rob Jones]

How would you therfore know if the co-ordinate you are looking at is listed in minutes or decimal. Yes you could figure it out if the number exceeds 60 but what if it is less?

Thanks for the info aswell

[rads]

Very good question.

It seems that more and more publications are using decimal degrees, but there is no hard and fast rule.

Anything with 3 digits in the last "bit" must be decimal as must anything over 60. Other than that, your in the dark.

Books that don't state the convention they are using are a pet hate of mine.

David

[Erin]

Decimal seconds should always be written to three decimal places. Therefore .045 would be decimal and not 45 seconds. Most GPS's use decimal so it should be possible to change your unit to take decimal instead.

Keith

[Simon Hawkins]

Have you checked the settings on your GPS as this may be set to seconds. Seconds are not used at sea so therefore check you have the system set correctly. Also make sure it is set to WGS84 Positions as the Datum as it it is not then the position you are given by the system will not be your actual position on the chart.

[Little Blue]

My LowranceM68C has a menu structure as follows

Menu, Menu, GPS Set Up, Coordinate system

once at this place you can toggle between Mins and seconds or decimal mins.

maybe yours is different but all the GPS's ive seen have this option.

[Pete7]

Are you sure the error isn't with the first zero? so instead of trying to enter
050 39 764 N, try 50 39 764 N as you can't have a line of latitude greater than 90 degrees.

Pete