Maps & satellites

[robo44]

Not sure if this has been totaly covered, but wanted to ask. I use my TomTom One 3Rd Edition, frequently and keep it updated by Tom Tom Home with the exception of my map. The map is over 4 quarters old.
I stick mainly to California driving, well established roads, and don?t see the need to update a USA map every quarter.
However, recently I noticed that my GPS is having issues with the satellites. It appears to me that the system is having issues tracking me and is off by 500 yards or more. In other cases, it puts me totally off the freeway. Not to mention take about 15 minutes to locate a satellite when I turn on the unit. The areas I am driving are well traveled and established roads not back country. It causes a problem and I miss my exits.

My question: What benefits are there in upgrading to a current Map?
What would cause my unit to start to have issues with tracking or the satellites?


Any suggestions to get the unit to calibrate better or back as it was? Used to be off about 25 feet and that was great, 500 yards or off on another road is no good.

 

[dhn]

When was the last time you got an updated quickgpsfile using Home?

 

[robo44]

I updated yesterday, but I regularly update using home at least every 5 days.

 

[dhn]

Use Explorer to delete everything in the ephem folder on your unit and see if that helps.

 

[robo44]

Ok I will try that -

 

[robo44]

Okay tried that yesterday deleted all the files in the ephem folder. The system took approximately 18 min to locate satalites and my location.

 

[dhn]

And, when you turn the unit off and turn it on again......how long to capture a signal?

 

[robo44]

Okay seems as if the unit now connects to the satalite, within 15 seconds, so this seems to have fixed the problem, and the range seems to be a bit better within 25 to 30 feet.

I used the system yesterday and only encountered on area that showed me off the road, but I was within 20 yards. So thanks for your help. I will try this for awhile.

Question, what is the ephem folder and what are the contents

 

[dhn]

The ephem folder holds the file of the latest qickgpsfile you dl using TomTom.

 

[robo44]

Just an update after 7 days of non-stop use, the unit is back to taking about 5-7 minutes to recognize the satellites. It may seem a bit odd, but 5-7 min seems like an eternity and we can't start our journey until the unit syncs up. While I have notice that the accuracy is a bit better, Id still like to know if 5-7 minutes to locate a satellite is standard, or is there something else I should do?

 

[dhn]

5-7 minutes is a long time after daily use to grab a signal. Did you do a unit reset? Does that help?

Have you downloaded a new quickgpsfix file?

 

[robo44]

I did not do a unit reset, and I did not download a new quickgpsfix file, in a previous post it was suggested that I empty the ephem folder. Since then it has not updated a nre quickgpsfix file

Are you suggesting that I add back the data in the ephm folder?

 

[dhn]

I'm just trying to figure out why you are continually encountering a satellite signal problem.

For some, a unit reset seems to help grab the signal faster.

For others, getting a new quickfix file speeds up the obtaining of the signal. I KNOW that getting the file is the opposite of what you did earlier (clearing out the folders), but I'm just grasping at straws here, trying to figure if it's a software problem, rather than a hardware issue.

 

[robo44]

Well I do appreciate your help with this .. thank you let me try a reset

 

[dwgsp]

I have not taken a quickfix update since the latest 140s firmware was released, and my unit consistently determines it's position in less than 30 seconds. I have to wonder if part of the problem that folks are having has to do with where their GPS unit is mounted. If it does not have a pretty clear view of the sky, it will take longer for it to lock on to the satellites.

/Don

 

[robo44]

Well, just for kicks , I reinstalled the files in the EPHEM folder, and got the latest quickfix, and what would you know, the system boots up in less than 10 seconds with my position. So, Im not sure what is happening, but for now, my GPS seems to be operating fairly well.
I did hit the reset buttton yesterday, so maybe that cleared out some junk?

Thanks to all for your suggestions