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This FAQ shows you how to find your location for use in our online
maps [1] (LocFinder) in one easy step.
* Use the GPS Lookup [2] facility and enter your address details,
after a short delay (about 5 seconds) you will be shown you a map
confirming the location you specified. Use the latitude and longitude
given to you above the map.
-------------------------
Below is the OLD howto entry, useful if the above method doesn't work
for you.
This FAQ shows you how to enter your location into the LocFinder [3]
node mapping database in four easy steps:
* 1. Use the web to find your location [4]
* 2. Convert DMS coordinates to Decimal Degrees [5]
* 3. Convert GDA94 coordinates to AGD66 coordinates [6]
* 4. Enter AGD66 coordinates into LocFinder [7]
1. USE THE WEB TO FIND YOUR LOCATION
For Victorian users, find your coordinates on the Victorian
Government's Land Channel Interactive Map
http://services.land.vic.gov.au/landchannel/content/interactivemap
[8]
When zoomed right in, the map will show individual property
boundaries, with street numbers. Find your location and look at the
bottom left corner of your browser window:
You need to use the coordinates marked as "Geographicals" - these are
your Latitude and Longitude, respectively.
Note that these coordinates are in the format DEGREES, MINUTES,
SECONDS.FractionsOfSeconds
YOU CAN NOT ENTER THESE COORDINATES INTO LOCFINDER [9] DIRECTLY!
The LocFinder [10] node database only accepts coordinates as DECIMAL
DEGREES.
Fractions of Degrees have traditionally been expressed as Minutes and
Seconds. One Minute is one 60th of a Degree and one Second is one 60th
of a Minute. Fractions of a second are usually written as a decimal
fraction.
In the above example our Latitude is 37 Degrees, 19 Minutes and 53.5
Seconds South (of the Equator).
2. CONVERT DMS COORDINATES TO DECIMAL DEGREES
Decimal Degrees simply use a decimal fraction to express fractions of
a degree. The Latitude in the above example is -39.33153 when
expressed as a Decimal Degree. Latitudes south of the Equator are
expressed as negative numbers.
You can use this online tool to convert coordinates in
Degrees,Minutes,Seconds (DMS) format to Decimal Degrees:
http://www.geology.enr.state.nc.us/gis/latlon.html [11]
Here is an example of how to use it:
Note that this tool returns the wrong coordinates if you enter your
degrees as negative degrees. Keep everything positive and add the
negative sign to the Latitude afterwards.
3. CONVERT GDA94 COORDINATES TO AGD66 COORDINATES
OK, now you have your coordinates in Decimal Degrees format. You
could enter these coordinates into LocFinder [12] now but your node
would appear about 200 metres Southeast of your real location.
Why? Because, to make matters more complicated, there are two major
coordinate systems in use in Victoria today - the newer GDA94/WGS84
system and the older AGD66 system. These coordinate systems differ
from each other by about 200 metres. The GDA94 system is being
introduced into all Australian Government mapping products and is
based on the worldwide standard (WGS84) for GPS receivers. The
Victorian Land Channel website that we just used to get our
coordinates uses GDA94 coordinates, as does the NodeDB [13] wireless
node database. But LocFinder [14] uses AGD66 coordinates.
So now we need to convert our decimal GDA94 coordinates to decimal
AGD66 coordinates. The Victorian Land Channel website has a tool to do
just that:
GDA94-AGD66 Conversion Tool [15]
Here's an example of it's use:
This is the result:
4. ENTER AGD66 COORDINATES INTO LOCFINDER [16]
Finally we have numbers that we can directly enter into LocFinder
[17]. If you're not there already, go to the Node Creation [18] page.
(or edit your existing nodes [19])
And enter your coordinates (AGD66 Decimal Degrees) like so:
5 decimal places is more than adequate for LocFinder [20]
Your node should now hopefully show up in the right location in
LocFinder [21]
Links:
------
[1] http://melbournewireless.org.au/maps
[2] http://www.melbournewireless.org.au/maps/gpslookup
[3] http://melbournewireless.org.au/?LocFinder
[4]
http://melbournewireless.org.au/#1__use_the_web_to_find_your_location
[5]
http://melbournewireless.org.au/#2__convert_dms_coordinates_to_decimal_degrees
[6]
http://melbournewireless.org.au/#3__convert_gda94_coordinates_to_agd66_coordinates
[7]
http://melbournewireless.org.au/#4__enter_agd66_coordinates_into_locfinder
[8] http://services.land.vic.gov.au/landchannel/content/interactivemap
[9] http://melbournewireless.org.au/?LOCFINDER
[10] http://melbournewireless.org.au/?LocFinder
[11] http://www.geology.enr.state.nc.us/gis/latlon.html
[12] http://melbournewireless.org.au/?LocFinder
[13] http://www.nodedb.com
[14] http://melbournewireless.org.au/?LocFinder
[15]
http://www.land.vic.gov.au/land/lcnlc2.nsf/childdocs/-418EED712A81C5AE4A256A0A0015CDC1-5DF1E2E5B878F6634A256A0A001DAC5C-5B923E73477D6D65CA256E5F0013D73B-E2E957070C9269184A2568B60015AC7B?open
[16] http://melbournewireless.org.au/?LOCFINDER
[17] http://melbournewireless.org.au/?LocFinder
[18] http://melbournewireless.org.au/nodes/create/
[19] http://melbournewireless.org.au/users/account/
[20] http://melbournewireless.org.au/?LocFinder
[21] http://melbournewireless.org.au/?LocFinder
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