TomTom GPS - time to locate

Baldlygo · Posted: Wed Nov 17, 2004 3:48 pm Post subject: TomTom GPS - time to locate

I am resonably impressed with my TT Bluetooth working on my HP1940 but on occasions I do have a fairly serious problem.

Reading the TT quick start guide it says "first you use the GPS reciever, it may take 45 minutes before it can provide a position"

When I start off from home I can set the position fairly quickly - but then I don't usually need help navigating down my own drive and street! I never want to leave my kit in view when I reach my destination so it is switched off and taken away.

However when I return four hours later to go home I find that TT does not know where I am again - usually for 10-15mins (sometimes never!). When in a strange area it is possible to go quite wrong in those 15mins!

I also have Memory Map installed an when I turn it on the TT GPS locates almost instantly. I switch off MM and fire up TT and find that TT then knows where I am. So I have taken to do this whenever I am in the range of my MM map. Unfortunately that range does not extend to most destinations so it is not an option when away.

Anyhow - If MM can locate straight away why can't TT? It just seems that the GPS is not seeing any satellites at all in the delay while MM sees them straight away.

To start MM first to get a fix is a bodge! If TT can't explain and fix the problem how about someone else writting the code to kick the GPS into action (like MM). This could be launched from a button - hey presto!

lbendlin · Posted: Wed Nov 17, 2004 5:16 pm Post subject:

TomTom is sometimes re-starting the BT GPS, resulting in the odd behaviour you see. The best solution is to not terminate the TomTom program, but simply switch the PDA off. This may help.
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Lutz

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Baldlygo · Posted: Wed Nov 17, 2004 6:03 pm Post subject:

lbendlin - "....simply switch the PDA off"
That is exactly what I have been doing.

I would be interested to know how other TT people get over this (if indeed they have the same problem). And also why MM fires up the same TT3 BT GPS instantly?

Robin2 · Posted: Wed Nov 17, 2004 6:12 pm Post subject:

If you start driving before your gps receiver has obtained a fix, it will take ages. My own receiver (Holux GM210) has started taking longer than it used to get a fix, but if I move off before getting the fix it can sometimes take half an hour before it locks on. But this is normal behaviour for a gps receiver, it needs you to be stationary while it is updating its data from the satellites which are in view, and this takes at least 45 seconds from a warm start. See Dave's replies to my query regarding long TTFF in the Holux thread
Robin

Baldlygo · Posted: Wed Nov 17, 2004 6:31 pm Post subject:

Hmmm....Thanks for that Robin.
If it means I have to sit in the car for 10-15mins before I move off then I am going to have problems!! Usually the people (whole family & grandchildren) are all waiting to wave goodbye and my wife is telling me to move off straight away before they all get frozen and all their homes heat escapes through their front door!
....also it would mean adding 10-15mins to all my journeys - thus quickly cancelling out any benefit of time saving with satnav.

While I have actually sat waiting for TT to locate I see NO signals from NO satellites - am I just suspicious in thinking it has not actually started doing anything yet. I say again...when firing up MM 2004 I start getting signals before I can set the option to see the GPS satellite output.

lbendlin · Posted: Wed Nov 17, 2004 7:23 pm Post subject:

Baldlygo · Posted: Wed Nov 17, 2004 9:32 pm Post subject:

OK .... I'm probably showing my complete GPS ignorance here but why does TT need to restart anything when MM just listens and locates more or less instantly?

lbendlin · Posted: Wed Nov 17, 2004 10:15 pm Post subject:

Excellent question - I have no idea why TomTom are doing it. Maybe they want to make sure the right NMEA sequences are sent.
_________________
Lutz

Report Map Errors here:
TomTom/TeleAtlas NAVTEQ

gilbem1 · Posted: Wed Nov 17, 2004 11:34 pm Post subject:

A colleague of mine had a similar problem re: satellite fix times at the start of journeys. He has a TT BT receiver and upon their advice, he let the power drain completely (which apparently effectively initiates a reboot on next power up), then re-charged for 2 hours, and has had a successful fix in a mtter of seconds for all subsequent startups ? Worth a try !

Baldlygo · Posted: Thu Nov 18, 2004 12:00 am Post subject:

Baldlygo · Posted: Thu Nov 18, 2004 6:26 pm Post subject:

Well I did as suggested and at home it does seem to locate much faster - in fact seconds! That was after turning off both PDA & TT3 BT rec - then tuning on BT rec. and PDA in that order.

So I will now have to try it out for real on my next trip away. Thanks to all for their help.

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