GDA co0-ordinates

[snakehorse]

Hello. This is my first post. I have just bought a Garmin Etrek 10. I have read the minimalist intrns in the manual and done some net research on GDA 94, 84 etc and read up on eastings and northings. I know how to express a four, six or eight digit grid location, but I have not found the answer to my question. My GPS unit expresses the grid ref as
15 G 0525444
5251834
I would be grateful if someone could tell me what these numbers represent. Which numbers are the actual grid lines on the map? Is the 52 Tas, where I am?
many thanks

[Gippsmick]

G'day snakehorse.

Your GPS is displaying the Universal Transverse Mercator grid with a full easting and northing.

This may help: http://jevans.pcug.org.au/Pages/Map%20Reading.htm

To get your six figure grid from this drop the 05 from the easting and use the next 3 digits 254, and drop the 52 from the northing and using the the next 3 digits 518.
Your grid ref is 254 251.

Your 8 digit grid ref is 2544 5183

Each number gives you a greater level of accuracy.

[bauplenut]

And remember to know the datum you are using with a map - otherwise you may be out by 200 or so metres. So if using GDA66 map, set the GPS to GDA66 as well - or you can adjust yourself if you know the correction figures (eg if GPS is set to GDA94 but you are using GDA66 map). If using WGS/GDA94 then set GPS to WGS/GDA94. From experience, it makes a significant difference when your map is different datum to the GPS.

[tastrax]

I would also be worried about the 15 G - that's way off in the Pacific Ocean off Chile

It should be 55G which would then place you at about Bonnington Road West Hobart

Here is a good reference re GDA / AGD - https://www.tasmap.tas.gov.au/static/content/GDA.pdf

[tastrax]

If you are using a TASMAP have a look in the bottom right of the map and there is a good explanation about the "universal Grid Reference".

Also check the grid in the bottom left of the map as there are a few extra numbers there that will make things a lot clearer if expressing your location with a full grid reference (that will match the GPS). Be aware that the leading zero on the easting is not on the map.

[snakehorse]

Thanks to all for the help. I will be now OK with the info provided by you. As a matter of interest I am using a GDA 94 Tasmap and set the Etrek accordingly. The 15 was 55, a typo on my part.