How Do I Project A Waypoint For My Cache?

[+robotman]

I am trying to set up an offset cache. I have the starting location (let's say "START") and then the cache hiding spot (let's say "HIDE").

 

1. What's the difference between Heading and Bearing?

2. How do I figure out what degrees to tell people to use to go from START to HIDE?

 

The distance I can figure out just from walking from one point to the other and seeing what the GPSr say is the distance. The Bearing and Heading seem to flip all over the place when I move around. I'm very confused!

 

I'm using a SporTrak Pro if anyone has specific instructions on how to figure out what Bearing (or Heading?) I should use.

 

Thanks.

 

John (aka Robotman)

[+welch]

1. What's the difference between Heading and Bearing?

2. How do I figure out what degrees to tell people to use to go from START to HIDE?

 

Heading the is the direction you're actually moving.

Bearing in the direction you should be moving to get to your target location.

Basically 180° is south, 90 east, 270 west, 360 or 0 is north. If you were using a compass and a map you would need to make sure to account for magnetic declination (the magnetic poles are not at exactly the same places as the actual 'top' and 'bottom' of the earth). If your using a gps to do this, you'll still need to specifiy if you're using true or magnetic (some gps have 'Auto' for declination, some you can input the varience to use).

 

Hmm, off hand I would say to mark a point at the the start and use the project waypoint function on the gps and guess at direction, you know the approx. distance, so after a few good guesses you'll know.

There may be a better method then guess and check, but I don't use the projection functions much.

 

oh, and you should consider using a distance that can be put into 'most' gps units. Some only go to like one decimal in miles, etc.

Edited September 13, 2005 by welch

[+Thot]

I am trying to set up an offset cache.  I have the starting location (let's say "START") and then the cache hiding spot (let's say "HIDE").

 

2.  How do I figure out what degrees to tell people to use to go from START to HIDE?

Set your north reference. Menu > Setup > North Reference (I would choose Magnetic but someone will probably jump in immediately to say you should use True.)

 

Go to HIDE.

Capture the coordinates.

Set these coordinates as your target (GoTo) waypoint.

Go to START.

Record the bearing and the coordinates.

 

On your cache description page explain whether the person should use Magnetic or True -- whichever one you chose. This is important in your location because there is a significant difference in northern California.

 

NOTE: Hold or hang or set your GPSr in a vertical position and in the same place for at least 3 minutes (5 is better) at both HIDE and START before recording readings.

 

In my opinion you should repeat this 3 times, preferably at different times of the day, but someone my well jump in to say doing this is pointless. http://factsfacts.com/geocachingsoft/Avera...Coordinates.htm

Edited September 13, 2005 by Thot

[+EScout]

Enter the coords for the start point and name it: "1start"

Enter the coords for the hide spot and name it: "1hide"

 

Go to your route function: Menu>Routes>Empty

You will create a route by entering the above waypoints (hit enter on the blank, add WPT-find by alphabetical.) When you highlight the second point, 1hide, it will show the distance and bearing to it from the first.

 

Be sure to set your North reference to degrees true (or magnetic) and Nav Units to miles/feet-or-yards/MPH or KM/KPH.

 

You can also use the PC program GeoCalc, or the Palm OS program Navigate. The advantage of these is that they will give you decimal degrees for greater precision. On your GPSr, if you want greater precision, use mils (6400 in a circle versus 360 degrees.)