TomTom One V3 Europe Latitude and Longitude Settings

uberalles

Hello All
I was wondering if you could help please.

My question relates to GPS on My TomTom One, specifically around the Latitude / Longitude readings when compared to a high level ordnance survey map.

My TomTom readings, whilst recognising where I am on a map, ie, correct street name, lists my GPS Latitude / Longitude readings as
53.21347 -1.61323

I also have a Garmin etrex GPS which correctly relates to the map with readings of
N 53.deg.12.485 W 001.deg. 36.489

These are my approximate home readings which according to Microsoft Virtual Earth Maps are correct and relate to both the same place.

However, I would like both systems to read as per my Garmin ETrex so that I can compare them to Ordnance Survey Maps.
Is there therefore a setting in my TomTom that requires updating?

My software details from my TomTom One V3 Western Europe are:-
app 7.166 (8497/080109) os:2332 v720.1802 western europe 1gb

I have tried contacting TomTom who sent me a link to lots of self help webpages that did not address the question.
Thank you for any help.

CHR15

If I understand you correctly, I believe the problem lies in the fact that Ordnance Survey Maps use a different positioning system to TomTom.

OS uses OSGB 36 but TomTom uses the now standard WGS 84.

This isn't really an application issue, but more with the GPS system. I dont know of any simple workaround.

For differences

http://en.wikipedia.org/wiki/OSGB36#Datum_shift_between_OSGB_36_and_WGS_84

BillScarab

Well on my Garmin Nuvi 250 I'm sure I can choose how I want the Lattitude and Longitude displayed, i.e degrees/minutes/seconds or decimal. I would have thoguht your Tom Tom would be the same. Have a look on www.pocketgpsworld.co.uk someone on there will know the answer.

Online manual here look at the section called set units, maybe that will do it.

uberalles

CHR15
Thank you very much for that. :beer:
At least now I understand why there are differences.
I would not personally have known the keyword to look up on Wikipedia to even contemplate finding an answer.

There is a lot to read/understand but I think I might be able to convert one reading to another having finally understood it.
Cheers.

uberalles

BillScarab wrote: »

Well on my Garmin Nuvi 250 I'm sure I can choose how I want the Lattitude and Longitude displayed, i.e degrees/minutes/seconds or decimal. I would have thoguht your Tom Tom would be the same. Have a look on www.pocketgpsworld.co.uk someone on there will know the answer.

Online manual here look at the section called set units, maybe that will do it.

BillScarab, thank you very much, it has worked by simply switching the Units to Minutes. Brilliant, cheers. :beer:

Now off to read the Wikipedia post to understand the differences in the 2 systems.

BillScarab

There is no difference, just different ways of showing the same data. It's like saying 5.475 km instead of 5 km 475 m.

What CHRIS15 is saying is correct but if all you're interested in is the display format it doesn't really apply. From memory there are three ways of displaying lat/long

decimal
deg/min/sec (with decimal fractions of seconds if required)
deg/min (with decimal fractions of minutes instead of seconds)

moneymass

If i'm reading your Question correctly...

BillScarab wrote: »

What CHRIS15 is saying is correct but if all you're interested in is the display format it doesn't really apply.

However, I would like both systems to read as per my Garmin ETrex so that I can compare them to Ordnance Survey Maps.

As said the geodetic framework that the OS uses is different to the system that your GPS receiver works in.

There are several reasons for this but the main point for users is that you can't just take coordinates that relate to one datum and ellipsoid etc and plot them onto a chart/map that uses a different system (i.e. OSGB36 and Airy ellipsoid). There can be positional errors from 00'm up to 000's of m depending on your datum shift etc

The OS have an excellent site explaining all you should need to know, as do the wiki articles.

http://www.ordnancesurvey.co.uk/oswebsite/gps/information/coordinatesystemsinfo/guidecontents/guide4.html

What you have to do with your TomTom I have no idea as I don't work with recreational receivers/work sector. I also have no idea what type of maps they use etc so bear that in mind.