TEN (10) YEARS!!!!
For all of us that are not too technically savvy 
Think of this as the "Idiot's Guide to 10 Years"
GPSr... Global Positioning System Receiver.... A device used to determine a position on the face of the Earth.
How it works..... A geocacher, places a container somewhere on the Longitude and Latitude grid on the Earth
They locate their position with their GPSr... but how does it happen? Did you ever notice that when you face one way, you're "here" according to your readout, but when you turn to the right or left - you lose or gain 20 - 30 feet?????
You seem to be moving around in a circle, but you're just standing there..... The explanation is difficult, but it can be stated that the GPSr receives time and distance data from ALL the GPS satellites that are within transmitting distance. It analyzes this data to determine "it's" position on Lat & Long.
When your body, some trees, a ravine, a building or any other object is blocking these radio waves; you and your GPSr can be a distance away from "where you think you are"
This has hardly any bearing on "Automobile" navigation, since buildings (Houses, stores etc) are usually larger than 20 ft wide...
.........But try and find that small 35 mm film container in the woods and
...we have a bit of an issue.
programmer64 once described it to me like this:
If, the cacher that placed the cache had a "bad signal" the cacher's GPS could have been showing coordinates that could be as far as 20 - 30 feet off.... If you go out and your GPSr has a bad signal, YOUR reading could be 20 - 30 ft off... You could be as far as 60 feet from the cache, when your GPSr says "You're 3 ft away"
EWWWWWWW!!!!!!
If you're walking through the woods and you get "close" to Ground Zero (GZ) don't look at the GPS!!! Look around for "Something out of place" Something that doesn't belong, or isn't "Quite right"
~~~~~ I experienced this phenomenon last weekend, as I stood "Right beside" a cache hide..... The cacher who I was with said - Where it it? - Reading the GPSr - I said "20 ft (pointing with confidence) That way!!!"... I moved, he shouted "got it"... It was 2 ft Behind me :( :( :( Someday I'll "Learn" :D
Now, this accuracy was not possible 10 years ago. The USA's Selective Availability was implemented to purposely degrade those signals so "everyone not military" would automatically have a built in 60 ft inaccurate position. Imagine looking for that small 35 mm film canister in a 120 ft circle!!! (60' error hider + 60' error finder)
In May 2000 this was rescinded and the present day accuracy remains standard. Click here for timeline: http://www.guysnamedkim.com/geocache/geocache_history.html
Well, there you have it, The "roots" of our game.... If you want to attend a "10 Years" event - Click here for "local" events..... and thanks for visiting!
Clear Trails and Good Finds!!!
~~ Mikey Ngauger
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