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Now I Am Tracking Waas #33 And Showing "d's"


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I posted on a previous thread that I can't see any "d's" on my 60CSx. I have only had my CSx for about one week. The usual WAAS satellite that has been trackable here in Indiana in the past is #35. However, #35 is being moved to the west and hence not trackable from my location. Well, today I was outside with my CSx and I began to track #33 just above the eastern horizon and my 60CSx is showing "d's"! Anyway, I thought I would confirm with my Nuvi 350 and sure enough the Nuvi began tracking #33; however, no "d's" were showing. According to other users, the Nuvi apparently does not show "d's" when tracking WAAS. Anyway, below are a couple of photos. I am beginning to feel a little better about my 60 CSx and WAAS. Notice how both units are displaying the exact corrdinates? Very interesting. By the way, is #33 one of the new WAAS satellites?

 

DSC00020.jpg

 

DSC00017.jpg

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Well, I just checked an apparently #33 is EGNOS. Interesting. So, I do believe that I was not actually receiving error correction. Anyway, I'll just wait for #48 to move into position.

 

I had thought that US WAAS was compatible with European EGNOS and recievers could use info from either/or.

 

Sort of yes and no. This is from a Garmin engineer who said the following about #33 (AOR-E):

 

I have used AOR-E (EGNOS) in the past, but the system broadcasts a "do not use" indication much of the time during developmental phases. AOR-E is visible from the East Coast of the US but again the corrections are of little value because the system does not transmit IONO correction outside the coverage area of its ground stations. Right now the US WAAS system is the only system giving reliable correction information.

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Well, I just checked an apparently #33 is EGNOS. Interesting. So, I do believe that I was not actually receiving error correction. Anyway, I'll just wait for #48 to move into position.

I had thought that US WAAS was compatible with European EGNOS and recievers could use info from either/or.

It is true that they are compatible. And you can receive the satellite ephemeris/clock corrections from EGNOS and use them in the US. However, the ionospheric corrections (which are the largest component of the position error) from EGNOS only apply to Europe.

 

On the other hand, the fact that the Garmin unit was displaying Ds for EGNOS data is a further indication to me that the Ds are for the ephemeris/clock corrections only. EraSeek and I had done a couple of experiments that tended to indicate that as well. It looks to me as if the Garmin units can be applying ionospheric corrections (once again, the largest WAAS corrections) without displaying Ds, and vice-versa.

 

That doesn't lead me to any great confidence in Garmin's WAAS implementation.

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Well, I just checked an apparently #33 is EGNOS. Interesting. So, I do believe that I was not actually receiving error correction. Anyway, I'll just wait for #48 to move into position.

I had thought that US WAAS was compatible with European EGNOS and recievers could use info from either/or.

It is true that they are compatible. And you can receive the satellite ephemeris/clock corrections from EGNOS and use them in the US. However, the ionospheric corrections (which are the largest component of the position error) from EGNOS only apply to Europe.

 

On the other hand, the fact that the Garmin unit was displaying Ds for EGNOS data is a further indication to me that the Ds are for the ephemeris/clock corrections only. EraSeek and I had done a couple of experiments that tended to indicate that as well. It looks to me as if the Garmin units can be applying ionospheric corrections (once again, the largest WAAS corrections) without displaying Ds, and vice-versa.

 

That doesn't lead me to any great confidence in Garmin's WAAS implementation.

 

Does EGNOS work with US ground based stations?

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Does EGNOS work with US ground based stations?

No. The EGNOS system has a network of ground stations in Europe. It's the European equivalent of WAAS. It models the ionosphere over Europe only, just as WAAS models the ionosphere over the continental US only.

 

Technically, I suppose that the EGNOS satellite could receive the correction data for the US and include it in the ionospheric model, but it doesn't.

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I also picked up #33 today with my 60csx. 10ft accuracy with D's, 11ft accuracy without D's. . .

Really? How did you measure your accuracy so well? I am impressed.

 

Oh, wait. you were using the "accuracy" number given by the GPS and treating it like it was an actual accuracy, weren't you? You know that the number doesn't represent the actual accuracy, right?

 

At any rate, you wouldn't expect your accuracy to improve much using the EGNOS satellite, since its main corrections are only valid for Europe.

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Really? How did you measure your accuracy so well? I am impressed.

 

Oh, wait. you were using the "accuracy" number given by the GPS and treating it like it was an actual accuracy, weren't you? You know that the number doesn't represent the actual accuracy, right?

 

Wiseass comment.

 

This sort of response is uncalled for and does not contribute to a helpful and friendly community.

Edited by YuccaPatrol
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Really? How did you measure your accuracy so well? I am impressed.

 

Oh, wait. you were using the "accuracy" number given by the GPS and treating it like it was an actual accuracy, weren't you? You know that the number doesn't represent the actual accuracy, right?

Wiseass comment.

 

This sort of response is uncalled for and does not contribute to a helpful and friendly community.

Actually I thought fizzy's comment is right on. Too many people seem to think the GPS's reported "accuracy" is a true measure of how far off the reading are. Think about it. If the unit *knew* how far off it is, wouldn't it just apply that correction to give an accurate reading? :anitongue:

 

No, that number is just an *estimate* of how bad the readings *might* be.

 

The only true way to know how "accurate" your GPS is, is to visit a reference station with known coordinates.

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It's still a wiseass comment. It is correct, but the observation could have been made in a manner conveying information, not derision!

Please note that my sarcastic comment was made in response to someone who wrote in another thread:

My non WAAS corrected accuracy was 11ft, with WAAS it was 10 feet!

 

I think people are getting bent all out of shape over this issue and we should all wait until Sat 35 is moved and operational again.

 

The difference between 11 and 10 ft accuracy is simply not even worth posting about.

I'd say the sarcasm was well-deserved.

Edited by fizzymagic
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It's still a wiseass comment. It is correct, but the observation could have been made in a manner conveying information, not derision!

Please note that my sarcastic comment was made in response to someone who wrote in another thread:

My non WAAS corrected accuracy was 11ft, with WAAS it was 10 feet!

 

I think people are getting bent all out of shape over this issue and we should all wait until Sat 35 is moved and operational again.

 

The difference between 11 and 10 ft accuracy is simply not even worth posting about.

I'd say the sarcasm was well-deserved.

 

Well, then you should go to the other thread and make fun of me there too since I was the one who said the comment so deserving of your derision. :D:D:D

 

My point was that these units do show d's when receiving corrections, but I did make the error of calling an EGNOS satellite a WAAS satellite, and so I certainly deserve whatever sarcasm you can fling my way. . .

Edited by YuccaPatrol
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Does EGNOS work with US ground based stations?

Technically, I suppose that the EGNOS satellite could receive the correction data for the US and include it in the ionospheric model, but it doesn't.

 

This is the proposed direction things are going. An integrated world wide system. But things are not there yet.

 

Current service areas for the ionosphere corrections:

nav1,1.jpg

Edited by EraSeek
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