A topic on the geocaching.com forums made me realize I need to add another point to this that I'd forgot to mention in earlier versions of this article. I make a mental note of the EPE values when taking these readings. I should jot them down, but usually I just remember them. If my EPE values are high, say 30 feet or greater, I come back at another time. If possible I try to only take readings when the EPE is 20 feet or less, preferably 13 feet. I didn't normally get an EPE less than 13 when placing a cache until I got the Garmin 60C. In the few caches I have placed I've never had to use readings when EPE values were as great a 30 and rarely greater than 20. If I ever have to I will mention it in the cache description. A decent EPE is important. A single reading at EPE 10 is likely to be better than the average of 3-5 readings at EPE 50. Here's my article on EPE.
Both my SproTrak Pro and Garmin 60C must be held vertical to get the best signal. I got tired of holding it, so I made this hook. It's surprising how many things it will hang on. The large end of the hook probably looks familiar:
I needed a way to combine all my readings into a single set of coordinates. That's what this program does. It works with coordinates in the typical geocaching format of degrees minutes and decimal minutes, like this:
N 29° 35.715 W 95° 05.051
I have revised the program from the original so you can enter (paste) coordinates in this format. This way you can import them from your GPSr using a program such as GSAK and paste them directly into the program. The original entry method is still supported and can be found near the end of this page. Data files saved using the original format still work and will import correctly into this version.
When you click "Plot" you get this display.
Normally I would only enter the decimal part of the minutes. In this example I would enter 715 and 051. In the very unusual case that you're near the minute change point, and some values have different minutes you will have to enter 4 digits. For example, if one minutes value were 35.999 and another 36.000 I would enter 5999 and 6000. You can enter the entire number if you want, but do not include the decimal and you must include 3 numbers after the decimal even if they're zeros -- e.g., 35999 and 36000.
When you click Plot you get a display like this
|The blue + marks are plots of the individual readings. The red + is the average of the individual readings. I this case I removed the outlying point on the far right. An outlier is a point that is far enough away from the cluster of other points it doesn't seem like it's really part of the group. You can delete points by right clicking on them. After removing the outlier from the above set you get the following revised plot and average.|
|If you don't think the average is a good center for the plotted
points you can click at the location you think is the best center of the
cluster and a green + will be put at the
location of your choice and the coordinates for that location displayed .
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