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Does Waas Do Anything In The Uk


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Just left my Geko outside the house (Northumberland) for an hour and I'm seeing 7ft (in)accuracy with lots of 'D's and 33 showing a good signal. Previously, I've only seen it for a few minutes. Maybe egnos is starting to go operational :laughing: Whether the figure means anything is another matter...

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I own a Magellan , and unlike Garmin , Magellan just accept the correction regardless of the "validity flag" status ....This caused a lot of problems until I discovered how to disable Waas ( its a boot up hidden menu)

 

Recently I retried enabling Waas and for a while all seemed well, however, occasionally , the "goto" compass needle would behave like it was moving through treacle , and generally the response was perceptibly slower with Waas enabled ....

 

So its disabled (again)

 

Any other Magellan users notice this?

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:yikes: I,m getting full lock and 5ft accuracy most of the time now here in Lancashire. :laughing:

ok, so from that i take it that it is active in the uk.

 

and to fruity, what was the point?

the point was that this has been discussed loads of times and we never realy know the answer so why dont you cheer up a bit and have some fun thats all its meant to be

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I own a Magellan , and unlike Garmin , Magellan just accept the correction regardless of the "validity flag" status ....This caused a lot of problems until I discovered how to disable Waas ( its a boot up hidden menu)

 

Recently I retried enabling Waas and for a while all seemed well, however, occasionally , the "goto" compass needle would behave like it was moving through treacle , and generally the response was perceptibly slower with Waas enabled ....

 

So its disabled (again)

 

Any other Magellan users notice this?

I've never disabled WAAS and never noticed the problems you've had (doesn't mean I haven't had them I suppose, just not noticed them).

 

Occasionally we do find a cache seems to be off by 10m or so but that happens WAAS on or off and is just a likely to be the behaviour of the placers GPS as ours or a combination of both producing cummulative error. Normally however WAAS on or off we find cache co-ords bang on.

 

FYI: Our GPS is a SporTrak Pro.

 

Jon.

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I asked the nice people at ESA about the whole issue and they replied today with this e-mail.

"First of all thanks for your interest in ESA programmes and particularly in

EGNOS. Indeed EGNOS works above UK and Europe but it is still in the test

phase however it will become progressively fully available and operational

this year. To know more about the current status of EGNOS you can refer to

the ESA navigation pages:http://www.esa.int/esaNA/index.html

From there you can go to the pages dedicated to EGNOS in general and you also

will find a link to the "EGNOS for professional" site.

I hope you will enjoy using EGNOS."

 

Best regards

Dominique DETAIN

ESA

dominique.detain@esa.int

 

So I guess it does work, in test phase.

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I asked the nice people at ESA about the whole issue and they replied today with this e-mail.

"First of all thanks for your interest in ESA programmes and particularly in

EGNOS. Indeed EGNOS works above UK and Europe but it is still in the test

phase however it will become progressively fully available and operational

this year. To know more about the current status of EGNOS you can refer to

the ESA navigation pages:http://www.esa.int/esaNA/index.html

From there you can go to the pages dedicated to EGNOS in general and you also

will find a link to the "EGNOS for professional" site.

I hope you will enjoy using EGNOS."

 

Best regards

Dominique DETAIN

ESA

dominique.detain@esa.int

 

So I guess it does work, in test phase.

Are you making this up???

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the site says (21st June 2005)

 

By early 2006, when operational stability is expected to be reached, the EGNOS open service will be declared formally available to the general public over Europe for non safety-of-life applications, free of direct charges. Today, the general public can already receive the EGNOS signal on a test basis.

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I've done my research, and I could be bothered to read it: and -

 

"In reality, however, the performance of this test bed is quite good achieving accuracies of the order of 1-2m in core of Europe".

 

Why can't I, in the flattest part of the UK, get it. Or see sat no. 33? I understand that Sat No. 37 may be on test but I'm getting very irritable. Not that it will do me any good of course.

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I've done my research, and I could be bothered to read it: and -

 

"In reality, however, the performance of this test bed is quite good achieving accuracies of the order of 1-2m in core of Europe".

 

Why can't I, in the flattest part of the UK, get it. Or see sat no. 33? I understand that Sat No. 37 may be on test but I'm getting very irritable. Not that it will do me any good of course.

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The WAAS system was really designed for aircraft flying over the US, or ships sailing at US latitudes. That is why it is based on satellites that are low on the horizon. GPS relies on satellites across the sky, but WAAS, and EGNOS rely on views of the southern horizon that many people will find a challenge on land at UK latitudes. As I have said above, I seriously doubt it will ever make a meaningful difference to caching - indeed - if every cache page would get me to within 2 meters of the destination, I would probably give up the sport as lacking much of the challenge - and what a joy for those determined to wreck caches - A WAAS enabled device would make muggling so easy!

Edited by Learned Gerbil
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If you are in range of others at the time they are transmitting error corrections and consistently receive them for long enough to download the almanacs (about 5 minutes), the Ds should appear. When the EGNOS satellites vanish (as they will!), the Ds will gradually disappear.

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In North Yorkshire, I can't remember receiving satellite 37 for long enough to get error corrections. Number 33 is the commonest one I see. Of course, you've got to be in the right place at the right time. A ginormous hill with a good view south is an advantage.

Edited by Omega2
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I had No 37 for 15 mins pretty constantly, No 33 came on and off and number 50 showed sometimes when either 33 or 37 was off - there wasn't enough room for all 3 to show at the same time. But no D's, except the big D over my head that said dissapointed. I see from the above though that 15 mins may not have been enough and it never went black, just grey.

 

I'll try again tomorrow.

 

By the way, since there satellites are to the south of me, does it help to hold the GPS at an angle to face the south?

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By the way, since there satellites are to the south of me, does it help to hold the GPS at an angle to face the south?

Check the manual of your GPSr to find out whether the antenna should be made vertical by holding the unit upright , as in the Magellan, or horizontal, as I believe the eTrex units are configured.

 

With respect to azimuth orientation, at our British Latitudes most of theGPS sats are to the South of us (for cachers North of Perth, they are all to the South of us!), so it makes sense to stand with your back to North to get the most satellite signals as the radio waves at GPS's frequency cannot pass through a human body.

 

For most locations in Britain, the WAAS/EGNOS satellite from which we receive the augmentation data is the InMarSat Atlantic Ocean Region East one. That's on a bearing of about 200° and is about 25° above the horizon, so it can make a difference if you ensure that your body is not blocking the sightline to that sat.

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no. 33 was the one doing it for me. took a few mins of standing still but once it locked on to that one all the d's appeared. twice now. will maybe try again today..see what time i've got.

That just worked for me on my 60C. I was out caching last night and saw accuracy to +/- 4 metres which suggested that it was working better. Just now, left it sat under a clear sky unmoved for 10 minutes and the accuracy is down to +/- 2 metres. Will see what happens next time I am out caching (tomorrow night maybe). :rolleyes:

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For most locations in Britain, the WAAS/EGNOS satellite from which we receive the augmentation data is the InMarSat Atlantic Ocean Region East one.  That's on a bearing of about 200° and is about 25° above the horizon, so it can make a difference if you ensure that your body is not blocking the sightline to that sat.

 

That's No 33 on the Garmin Units. From where I am (N.Yorks) I seem to get a clearer signal from No 37 (which is ARTEMIS). I believe this is still only sending test signals at the moment so my Garmin (V) doesn't try to use them :lol: .

 

The signal from 33 (AOR-E) seems too irregular to get a good fix from here so I am among the many still to see those lovely little Ds. What I need to find is a lovely country pub with a south-facing beer garden and a clear view. :):rolleyes:

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The WAAS system was really designed for aircraft flying over the US, or ships sailing at US latitudes. That is why it is based on satellites that are low on the horizon.

The North American WAAS was indeed conceived for aircraft at US Latitudes, including Alaska!

 

The reason why both WAAS and the new European equivalent use such Southerly satellites for the datalink is quite simply that there is only one Latitude at which it is possible to have geostationary sats and that's the Equator.

 

The Longitude of the sat is quite important for how high in the sky it appears to be from any given point. For example, for us in the North and North West of Britain, the Indian Ocean sat is too low in the sky to be of much use, so we have to use the AOR-E one instead.

 

If they chose an orbital inclination for the data sat of anything other than zero, they would have to have a fleet of sats to maintain 24 hour coverage which would obviously multiply the cost. That's why they opted for geostationary satellites for the datalink.

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That's No 33 on the Garmin Units. From where I am (N.Yorks) I seem to get a clearer signal from No 37 (which is ARTEMIS). I believe this is still only sending test signals at the moment so my Garmin (V) doesn't try to use them :lol: .

 

The signal from 33 (AOR-E) seems too irregular to get a good fix from here so I am among the many still to see those lovely little Ds. What I need to find is a lovely country pub with a south-facing beer garden and a clear view. :):rolleyes:

There seems to be no rhyme or reason to this...I too am in North Yorkshire and have never seen Sat 37. My Venture will track Sat 33 but has never got full lock (i.e. never gone from grey to black). I suppose I will just have to keep trying, thankfully it hasn't hindered my hunting (work does that job nicely!!).

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When Artemis was launched she suffered from a failure of an upper stage booster which put her into a useless orbit.

 

The program managers had to take a decision on whether to hope that the craft could be coaxed into a useful orbit, and they decided to go for the tried and reliable InMarSat birds for the EGNOS (actually, ESTB, but let's not get picky) testing. The propulsion systems which have been used to rectify the erroneous orbit were never designed for such radical manoeuvring and it's a great credit to the operators to have made a silk purse out of a sow's ear.

 

Most of the ESTB testing work has been with the IOR sat, with some other work done using the AOR-E one. That's the one wghich is most useful for us in most parts of the UK.

 

The signals transmitted by the newly recovered Artemis have a been a bonus, but there have been a (very) few periods when it has been available to us, when compared to the AOR-E one.

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There seems to be no rhyme or reason to this...I too am in North Yorkshire and have never seen Sat 37.  My Venture will track Sat 33 but has never got full lock (i.e. never gone from grey to black).

On some receivers, the "signal bar" remains greyed out, and never turns shaded black, even though differential corrections are being received and applied.

 

This is because many models (of Garmin) expect the GEO satellite to be transmitting ranging information, in addition to corrections.

 

Satellite AOR-E (PRN 120, Garmin #33) is currently transmitting corrections without ranging, so the behaviour you see is consistent.

 

-Wlw.

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There seems to be no rhyme or reason to this...I too am in North Yorkshire and have never seen Sat 37.  My Venture will track Sat 33 but has never got full lock (i.e. never gone from grey to black).

On some receivers, the "signal bar" remains greyed out, and never turns shaded black, even though differential corrections are being received and applied.

 

This is because many models (of Garmin) expect the GEO satellite to be transmitting ranging information, in addition to corrections.

 

Satellite AOR-E (PRN 120, Garmin #33) is currently transmitting corrections without ranging, so the behaviour you see is consistent.

 

-Wlw.

Thanks for the reply Wlw, one more question...My unit is not showing the magical D's either. Is this also normal? it doesn't seem to be making any difference to my accuracy (best is usually 5m). Perhaps I just have to wait until the sat becomes fully operational. :D

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Here's what I normally (well, often) see on my Garmin GPS V:

 

0d38f85f-3650-4847-ad98-7676e8a79ecf.jpg

 

I'm not complaining about the 15ft accuracy - plenty good enough for caching ;) - but it's really frustrating when you consistently get reception of the EGNOS sats but the unit refuses to accept the corrections. :D:D

 

BTW when I took the above photo I had been stationary for about 20 mins and had been 'seeing' the EGNOS sats all day.

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I'm not complaining about the 15ft accuracy - plenty good enough for caching :D  - but it's really frustrating when you consistently get reception of the EGNOS sats but the unit refuses to accept the corrections.  :D  :D

If you asked Garmin about this, they would tell you that your receiver is operating correctly, and in accordance with the agreed industry standard.

 

Which is correct.

 

If you asked them about the EGNOS/ESTB signal, they would tell you that the current signals are NOT compliant with the final agreed standard and that's why some Garmin units don't recognise them.

 

Which is also correct.

 

If you asked the European Space Agency (or their contractor: ESSP), they would tell you that the systems are still under test. They might refer you to this web page. The page is deliberately written in gobbledygook, so that hardly anyone can understand it. They would like you believe that the systems WILL BE compliant with industry standards, one day, but they don't want to talk about it.

 

Both the ESA and Garmin would be happy if you (and I) didn't ask them any more awkward questions about this whole thing... ;)

 

-Wlw.

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I just wish their units acted with some consistency! Clearly Garmin are capable of making their gpsrs accept the test signals and I assume it's only a firmware tweak to make any WAAS-enabled unit do so. Perhaps they feel that some units are more likely to be used in 'safety critical' situations; I know this range is popular with aviators (with one model, the GPSIII-Pilot specifically made for this market), so shouldn't give any augmented readings until the systems are certified.

 

Shouldn't complain I s'pose - it's a well made and reliable unit which delivers excellent performance under non-augmented conditions and Garmin are generally a really good company to deal with (except, obviously, on this subject).

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Perhaps they feel that some units are more likely to be used in 'safety critical' situations; I know this range is popular with aviators (with one model, the GPSIII-Pilot specifically made for this market), so shouldn't give any augmented readings until the systems are certified.

I have no doubt that you have put your finger on it.

 

-Wlw.

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Just in case those with Garmin units having difficulty in in getting the D's and have not read this taken from the Gps information site : "Be sure that your GPS is set to normal mode (not battery save) for this procedure. The nature of WAAS corrections precludes its use in Garmin battery save mode ".

 

Dave

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  "Be sure that your GPS is set to normal mode (not battery save) for this procedure. The nature of WAAS corrections precludes its use in Garmin battery save mode ".

 

That statement is actually very misleading: At least with my unit 'battery save' mode stops all satellite reception and is intended for 'indoor use'!! :D Presumably this is to enable route planning without the unit wasting energy trying to locate all those pesky satellites! :):D

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I took the statement to mean : If you are not in normal mode useing a Garmin gps you are unlikely to get any waas correction,or am I reading it wrong ??

Dave

I suppose that technically you are correct.

 

You would also be correct to extend this and say that: "if you were not in normal mode you would get no locational information at all"; so definitely no WAAS correction! :D

 

At least this is the case with the GPS V. Maybe other Garmins are different.

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That statement is actually very misleading: At least with my unit 'battery save' mode stops all satellite reception and is intended for 'indoor use'!! :D Presumably this is to enable route planning without the unit wasting energy trying to locate all those pesky satellites! :):D

I'm probably wrong but I was under the impression that 'battery save mode' just restricted the GPR reception to satellites that were 'high in the sky' not stop ALL satellite reception.

If I need to have my Legend on indoors I can select the 'Use with GPS off' option.

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That statement is actually very misleading:  At least with my unit 'battery save' mode stops all satellite reception and is intended for 'indoor use'!!  :D    Presumably this is to enable route planning without the unit wasting energy trying to locate all those pesky satellites! :)  :D

I'm probably wrong but I was under the impression that 'battery save mode' just restricted the GPR reception to satellites that were 'high in the sky' not stop ALL satellite reception.

If I need to have my Legend on indoors I can select the 'Use with GPS off' option.

I thought that in BS mode the gps received signals some thing like every 4 seconds instead of every 1 second in normal mode but still had access to all visible sats and as you say you can turn the gps off indoors

Dave

Edited by oddsock
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Some possibly useful information for Garmin iQue 3600 owners ONLY...

 

There is empirical evidence that the iQue 3600 will not use the current ESTB signal for differential corrections unless the interim software patch 5.2.1r3 patch1 is installed.

 

This can be downloaded from the Garmin website, HERE. This patch only applies to the iQue 3600 unit.

 

You may THINK that you have already installed the patch, but note that it needs to re-installed after a hard reset.

 

In operation, the unit may "skip" satellite #33 without acquiring enough data for it to be recognised as a (sort of) valid signal. It may be necessary to switch the unit off, and on again, at intervals of about ten minutes before the unit gets the part of the transmission which it recognises as useable. The reason for this behaviour is not known.

 

It is necessary for the iQue to receive the whole of the WAAS-type signal error-free, before all the corrections can be applied. This may take as long as half-an-hour, at first try in real-world operation.

 

Other information: Like many Garmin receivers, the iQue seems to have a preference for corrected satellite data, when not all sats are being corrected. This may mean that the overall accuracy of the solution may be WORSE under this condition.

 

The unit is very conservative about the validity "lifetime" of the corrections it receives. If the WAAS/EGNOS/ESTB signal is lost, an iQue will cease corrections within two minutes - even though the data should be valid for much longer than that. The reason for this behaviour is not known. (Again. :D )

 

-Wlw.

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It looks like my comments on "battery save" mode is applicable only to my unit. I notice that on the most recent manuals Garmin don't use that term and refer to it as "Demo" or "Simulator" mode.

 

Still can't get EGNOS though!

What version firmware are you useing?

Dave

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2.50 which I'm certain is the most recent. I've read somewhere that if you can find an older version and roll-back then it is more tolerant of correction data.

 

IMO the benefits of the latest version (eg via points for routing) would outweigh the benefit of EGNOS though so I probably wouldn't go back anyway.

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2.50 which I'm certain is the most recent.  I've read somewhere that if you can find an older version and roll-back then it is more tolerant of correction data.

 

IMO the benefits of the latest version (eg via points for routing) would outweigh the benefit of EGNOS though so I probably wouldn't go back anyway.

Yep ! thats the latest one ,Oct 2003 .So thats my theory out of the window then.

Dave

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