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i'm hoping this is the right place to post this because i'm leaving on a private boat early in the morning. i have a hand held gps system that i was going to put a few numbers for known places at catalina. if i mark a spot using my gps it comes up in this format...33^12.345. when i look on any website or gps map the numbers come up like this 33^12.34. my question is this. if i get some numbers off the internet and the last set of numbers which is "seconds" has only 2 digits should i just add a zero at the end?


edit: i let my better half take a look at and see if she can figure this out for me. we came up with this. my gps only appears to record degrees and minutes and NOT seconds. so when i physically mark a spot while on the water it comes up as 33(degrees)12.345(minutes). so when i look up something on the internet it typically comes up 33(degrees)12.34(minutes). i think its the same if i just add the zero at the end of it. hope this makes sense.
 

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I don't think it's that simple.
EXAMPLE using Maptech.Com

33.20.35 & 118.19.02 equates to 33.20.597 & 118.19.033
I don't remember the algorythm for converting either.

Maybe someone will chime in with the conversion formula.

Man am I watching a great Pink Floyd concert at the moment! :7

John.
Parker 2320 'FloMar'.
 

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>I don't think it's that simple.
>EXAMPLE using Maptech.Com
>
>33.20.35 & 118.19.02 equates to 33.20.597 & 118.19.033
>I don't remember the algorythm for converting either.
>
>Maybe someone will chime in with the conversion formula.
>
>Man am I watching a great Pink Floyd concert at the moment!
>:7
>
>John.
>Parker 2320 'FloMar'.

Some GPS's display degrees.minutes.seconds and some display degrees.minutes.hundredths-of-minutes. You need to know which you have. If you have the first kind, you divide by .60 to get the second.

33 degrees 20 minutes 35 seconds
equals
33 degrees 20.583 minutes.

because 35/.6 is 58.333333333...
 

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Logical question.

First, GPS receivers can be set to display in one of two formats:

1. degrees, minutes, seconds OR
2. degrees, minutes, tenths or minutes

The most commonly used format is the latter.

Now for the number of digits displayed. When GPS became WASS enabled most manufacturers began showing the tenths, hundreds, thousands and tenthousanths places on their displays in order to provide the accuracy available from the enhanced signal.

To answer your question: If your Catalina numbers only go the "hundredths" place, then just insert "0's" for the final two digits. Your accuracy will be limited to around 300' but are adequate for most navigation purposes.
 

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ok, i understand how to convert the tenths to seconds. but how are the coordinates recorded on a chart. are they in decimals to the tenths or hundredths or are they in seconds. i have a chart from fishnmaps.com. the coordinates are displayed such as example for newport canyon is 33 degrees 55.44n by 117 degrees 55.96w. does this mean that the seconds are recorded in decimal form and that i need to convert it? must be because the "seconds" would only go up to .59 before it would add another minute to the coordinate, right? if this is true that charts give data in tenths or hundredths then i should probably format my gps to read these cooridates properly. right?

monty
21' striper
jake's dream
 
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