Force TomTom Current Position

[peret2000]

Hello,
Is there a way to specify TomTom (navcore 8.562) what is my current position, modifying some file, so that gps signal can be detected quickly?
I guess the closer you are to the position the gps thinks you are, the quicker you start receiving radars signal.
I guess TomTom stores its last known position somewhere in a file.
So, If I know where I will be when I switch the gps on, and the coordinates, I think that telling TomTom that position, the radar signals will be received earlier.
Is it true, and possible?

 

[dhn]

When was the last time you connected to Home to get the latest gpsquickfix file?

 

[mikealder]

What radar signals are you thinking of, a TomTom doesn't receive any radar transmissions at all - Mike

 

[kj6fk]

As dhn suggested, just connect the device to HOME and you'll be offered QuickGPSFix, which is the Ephemeris data that allows the device to find GPS satellites faster. GPS satellites do not use a radar- it uses a CDMA broadcast signal.

 

[canderson]

... just connect the device to HOME and you'll be offered QuickGPSFix...

.. and if you are not offered a QuickGPSFix, let us know. It is not uncommon to have received an ephemeris file with a bad internal expiry date that prevents you from receiving any new files. We can help you to fix that easily by deleting the 'old stuff' from your unit and PC.

 

[peret2000]

I connect to get the gpsquickfix updates very frequently, and I do not have problems with it. The updates works ok.
I do not think the problem is to update satellites positions (by the way, when I said radar, I meant satellites, obviously).

Maybe you have not experienced delays receiving and processing satellite signals correctly.
I notice it when I start usign the GPS far from the place I last used it.
Regards

 

[Arno]

I know exactly what you mean but have no solution.
Once last year I drove all the way from Lake Placid to Tupper Lake before I got a satellite connection.
For two years it was fine but after that trip (six days without QuickGPSfix) it has remained spotty even if I leave the house immediately after a download/install.

 

[mikealder]

If you move long distance between using the device, usually this involves flying then time to attain a position fix will be increased the first time you use the device, it can take as long as twenty minutes with the device sat stationary, as soon as you start to move this compounds the problem the device has in trying to work out where you are - Mike

 

[canderson]

I
I notice it when I start usign the GPS far from the place I last used it.
Regards

As Mike says, and I will second, this is perfectly normal behavior for any GPS receiver. When first turned on, it makes assumptions about where it is, only to discover that the 'almanac' data that it had acquired when last used no longer seems to match any of satellites that it sees. It then must wait until it can receive a full set of new location vs. time (almanac) data from one of the satellites until it has some idea what to expect where it is now located.

Once it has done this, and provided you do not move far away or wait many days between use, it can use that almanac data that it had previously received to know what satellites to look for quickly instead of constantly scanning for all of them to see who's 'in town'.

 

[Rick F.]

I got a tip from TomTom a long time ago that even though I might have "deleted destination" ? to leave the TomTom on until I arrive my destination. This way TT keeps track of the satellite positions. So next time I turn it on it finds the satellites quicker. I've done that and it does seems to help.

 

[peret2000]

Thanks to everybody.
Your experience/comments help to better understand the behaviour.

I have got this other comment:
"If you have your gps off and then travel to a new location and then want to get a satelite fix, the best I have found is to plot an A to B navigation from some POI that you know is nearby. On one trip this was the only way I could get a satleite fix on mine, and my Quickfix is up to date. It also helps if you are not moving, and have no large buildings etc. near your position."
That may help. I wil try, although with your comments I do not think so:
Planning a trip does not mean to know where the satellites will be at destination.