help please having trouble entering gps marks

[solwota]

this may be a stupid question as i am new to the world of gps. i don't understand how to translate gps marks which are in minutes degrees and seconds. i assume the third group of digits which need a decimal point added somewhere as there should never be more than 60 seconds and in an example set of marks ie. 27 11 430 153 06 257 (PHIL Ts all time favorit marks thread) there appears to be more than 60 seconds. i know this is a standard method of displaying the the data i just don't know how to decipher it. my humminbird gps won't accept these marks as is and a google earth search has nill result.
can some one help please

thanks
richard

[Cruiser]

Richard, I think you'll find those marks are in Degrees, Minutes and decimal Minutes. Like you say you can't have more than 59 seconds.

So latitude 27 11 430 would be referring to 27deg 11.430 minutes and the longitude 153 06 257 would be entered at 153deg 6.257 minutes.

Don't forget to enter the latitudes as either a negative number or indicate South in some way.

Degrees and Minutes (with decimals) is probably the most common way of entering and displaying GPS marks in marine and aviation. The manual for your Humminbird should tell you what the format is (and you can probably change it in a menu somewhere).


If you do need to convert...

Decimal Degrees to Degrees & Decimal Minutes: take off the whole number of degrees and then multiply the decimal part by 60 to get the minutes.

Degrees & Decimal Minutes to Degrees: Divide the Minutes by 60 and add the result to the degrees.

Degrees & Decimal Minutes to Degrees & Minutes & Seconds: take off the whole number of minutes and multiply the decimal part by 60 to get the seconds.

Degrees & Minutes & Seconds to Degrees & Decimal Minutes: Divide the seconds by 60 and add the result to the minutes part.


Hope that helps (or confuses),

Chris.