Place misrecognition

[Wingcowyn]

Hi,
I have an old Go 700' which is not used all that often. I noticed that when I took it out, it took 20 mins to find a GPS signal.
This time I used it it stated that my destination was a place that was 10 miles before I had actually reached it, telling me that I had reached my destination 10 miles before I actually did.
Anyone with any suggestions?
Thanks,
Peter.

 

[Arno]

This time I used it it stated that my destination was a place that was 10 miles before I had actually reached it, telling me that I had reached my destination 10 miles before I actually did.

I don't quite follow.
Can you tell us step for step what you did and what the result of each action was.

 

[- et -]

Hi,
I have an old Go 700' which is not used all that often. I noticed that when I took it out, it took 20 mins to find a GPS signal.
This time I used it it stated that my destination was a place that was 10 miles before I had actually reached it, telling me that I had reached my destination 10 miles before I actually did.

I am not surprised that your device took a long time for its first fix after being switched off for an extended period. The GPS satellites are not in perfectly unchanging orbits, but in orbits that drift with time. Accordingly, when attempting to get a fix quickly the GO 700 refers to a look-up table that needs to be updated periodically.

Your GPS can get a fix without having a recent look-up table, but will take much longer to do so. Since your GO 700 had not been used for some time, its look-up table was out of date, and it took much longer for your GPS to determine your location.

On the other hand, I do not see why you should be getting the location error that your described. Is there any chance that you gave your GPS a destination with a name that is very, very similar to your actual destination, and did not notice this?

With best wishes,
- Tom -

 

[Wingcowyn]

Thanks Arno and et,
I simply typed in the destination as usual Arno, starting with the name of the place and then settled for anywhere in the village since the street name that I was interested in was not listed in my tomtom.
When it came up I thought that It was rather a quicker journey than it should have been. As the journey proceeded I could see that there was some problem, as I knew it was further than indicated on the machine. It then indicated that I had reached my destination as I passed through a village about 15 -20 miles before reaching the destination that I had typed in. This had a completely different name to my destination so there was no question of mis - typing.
At my destination, I typed in my destination again and it seemed to want to take me back to where it originally stated wrongly was my destination .
I have not updated it for years, so perhaps I should try that. I did not think that that would account for this problem though. I did think of selecting restore factory settings or to reset the machine, in case that would have some effect, but then I would lose all my stored locations.
I did not realise that there was a problem with shifting satellites et, and so that certainly would account for its initial slowness in locating them.
I assume that if it is used regularly, then it adjusts itself to the changes in position automatically.
Thanks,
Peter.

 

[Arno]

Peter, I once had a problem with satellite acquisition on my 930. driving for about 17 miles from a place to which it had guided me properly the night before.

If you would like I gladly try your departures and destinations, keeping in mind that I cannot program from Current location, only using Route A...B from over here.

You can send the data to my eMail address if you do not appreciate all and sundry to know your locations. (I do not like PMs, use (e-mail address removed) instead.)

If that shows different results you can still take the drastic step of a factory reset.
I don't know the 700 but presume you connect via Home.
If you make a complete Windows back up to your computer you can always copy back your ITNs, custom POIs and the mapsettings.cfg file, losing Recent destinations only.

 

[- et -]

I did not realise that there was a problem with shifting satellites et, and so that certainly would account for its initial slowness in locating them.
I assume that if it is used regularly, then it adjusts itself to the changes in position automatically.

That is the way it is supposed to work. As I understand it, an updated table of satellite positions is periodically transmitted to your device, so the GPS can start looking for the satellites from very close to their correct locations.

FWIW, a user can encounter similar behavior if the GPS is turned off and then moved a long distance before it is turned on again - because the GPS uses the satellite location table assuming that it is still where it was when it was turned off. After it does not find the satellites where it expects, it starts a general search that takes much longer because it has to search a much wider area for the satellites.

(I just realized that my wording implies that the GPS is using a directional antenna, which is not the case. The "search" is an attempt to match incoming data with a location that is compatible with what is being received from multiple satellites.)

With best wishes,
- Tom -

 

[Andy_P]

From the symptoms you've had, I can't really spot any connection between the two problems...

Did you have a GPS signal lock when the destination problem actually happened?

Any change you can tell us the name of the destination you typed in and the name of the village it was taking you to instead? (Don't post any precise personal details though!)

 

[Wingcowyn]

Thanks Arno, Tom and Andy,
I am not much of a technocrat, so I don,t quite understand what you would like me to do Arno. I apologise if this sounds stupid.
I am away from home at the moment and whilst I can access the Internet I am unable to send emails at present.
I have tried my Tomtom out a few times on short distances now and it seems to be OK, except that it has lost the GPS signal a few times for a minute or so.
It now recognises that I have reached my destination, Weston Rhyn, since if I type it in it tells me that I am here.
Curiously, it cannot find the village of Cefnbrynbrain, where I started my journey from, which seems strange that this is not included in its maps. This is not my home destination I should add.
Thanks,
Peter.

 

[Arno]

Curiously, it cannot find the village of Cefnbrynbrain, where I started my journey from, which seems strange that this is not included in its maps.

Neither my TomTom not Google can find Cefnbrynbrain.

They don't have any problems to drive from Cefn Berain to Weston Rhyn.
(TT attachment below, Google http://goo.gl/maps/Qg93F )

 

[canderson]

@Arno
Did you try it as "Cefn-Bryn-Brain"? That's how Teleatlas shows it in Swansea.

 

[Wingcowyn]

Thanks Arno and candlerson.
I have tried it your way candlerson, but it still cannot recognise it. Strange that neither it or google can recognise the place. It is quite a small village, but it has its own school, or it did before it was recently closed. It is plainly marked on OS maps.
Thanks,
Peter.

 

[Arno]

Did you try it as "Cefn-Bryn-Brain"? That's how Teleatlas shows it in Swansea.

I have tried it your way candlerson, but it still cannot recognise it. Strange that neither it or google can recognise the place. It is quite a small village, but it has its own school, or it did before it was recently closed. It is plainly marked on OS maps.

First off, no, I had not tried it like that.
Reason, when I entered the origin for the A...B and it auto completed Cefn Berain thus it was soooo obvious that Peter had misspelled it and I took in from there.
The only return in Google maps for the original spelling is a primary school in Cwmllynfell, a village 17 miles north of Swansea.
I did get to Swansea once, coming from Shrewsbury and happening upon the 0-4-0 Dougal which I had just seen two months before on the cover of Model Engineer a friend had lent me. Standing cold outside of town with no one around. Can't find that blasted picture of me on it right now.

Anywho, inputting the proper name of the town brings the proper route.

 

[canderson]

@Wingcowyn
Just used my Via 135 with a current W Europe map (910).

Search:
Requested UK
Typed only "Cefn"

Was rewarded with the following...

Cefn (Sanit Asaph)
Cefn Berain (Llannefydd)
Cefn-Brith (Cerrigydrudion)
Cefn-Bryn-Brain (Cwmllynfell)

and a host of others ... but as you can see, the one you wanted popped up in the #4 position. I'd recheck your spelling or perhaps the age of your map.

And I still maintain the the Welsh are vowel challenged!

 

[Arno]

Search:
Requested UK
Typed only "Cefn"
Was rewarded with the following...

Cefn (Sanit Asaph)
Cefn Berain (Llannefydd)I

I don't believe you.
Me thinks you were offered Cefn (Saint Asaph) and then the top half of Cefn Berain (Llannefydd).

Double clicking on that was good enough for me, as posted above, to presume a misspelling by Peter.

 

[canderson]

I think I was offered exactly what I typed. Surely you don't think a boy from Colorado could possibly have made those extraordinary Welsh names up?

 

[Andy_P]

As I start to type in the suggested "Cefnbrynbrain", after four letters my GO940 (on v910 maps) is already offering these results on the first scree: (a slightly different to canderson's list!)

I presume one of those is the correct place? But it looks like TomTom may be using the precise Welsh spelling and the OP may be using an Anglicised version?

Therefore no real problem with that placename?
Or something that has been improved on more up-to-date maps than the OP's 910 is running?

---------------------

Going back to the "true destination was 10 miles past the indicated one" problem... is "Cefnbrynbrain" the place you ware trying to go to?

EDIT: or was the problem place "Weston Rhyn" which you mention in one of your other posts?





.

 

[Andy_P]

For completeness: I get no results for candersons "Sanit Asaph" (I presume a typo there!) and I get no mention of "Saint Asaph" in ANY of the results for "Cefn...", but typing "Saint As..." finds it immediately.

 

[canderson]

Yes, a typo on 'Saint'. Here's how my first 5 look:

 

[Arno]

Just used my Via 135 with a current W Europe map (910).
Search:
Requested UK
Typed only "Cefn"
Was rewarded with the following...
Cefn (Saint Asaph) [corrected typo]
Cefn Berain (Llannefydd)
Cefn-Brith (Cerrigydrudion)
Cefn-Bryn-Brain (Cwmllynfell)

Surely you don't think a boy from Colorado could possibly have made those extraordinary Welsh names up?

No, laddie, I think it is the rarified air that did not make you report what you actually saw after just typing "Cefn".

To confirm, I too used the Via 135 with the v910 WE map.
The attachment below should corroborate my second line in post #14.
;->)

 

[Wingcowyn]

Thanks Arno, canderson and Andy P,
On entering Cefn on my Go 700 it brings up a number of Cefn's but not Cefn Bryn Brain. I thought that it didn't bring it up the place when I tried it canderson's way because I had omitted to put in dashes, simply leaving a space between the 3 words, but on checking my machine now, I see that it does not allow me to put dashes in place names. I suppose the reason that it does not come up on my 700 Go , but on other machines is the fact that their maps are more updated than mine.
This probably was not the cause of the journey to Weston Rhyn ending in a place called Pant some 10 - 15 miles short of the proper destination.
I have not updated the software on my Tomtom for years and will try doing that and see if this improves things.
Thanks,
Peter.