Email from Raymarine re A65

[BocaDon]

I just received the following email from Raymarine;

"The Federal Aviation Administration (FAA) recently decommissioned two WAAS GPS satellites (PRN 122 and PRN 134) and activated two replacement satellites (PRN 135 and PRN 138). Raymarine’s A65 and A60 do not recognize satellites 135 or 138 when used in conjunction with the supplied RS12 GPS sensor.

The A65 and A60 continue to receive the standard GPS signals using the supplied RS12 sensor and therefore are safe for navigation. As always, these products are an aid to navigation. It continues to be the user's responsibility to use caution, sound judgment, official government charts, notices to mariners and proper navigational skill when using this or any other electronic navigational product.

If you are not content with standard GPS position accuracy, there is an opportunity to upgrade the A65 and A60 display to receive WAAS accuracy. Please click here to see the steps on how to upgrade the A65 and A60 using a RS125 GPS antenna.

Kind Regards,

Raymarine Product Support"

I like their choice of words, "there is an opportunity to upgrade". The "opportunity" will cost about $300 for a RS125 with no special discount being offered.

My question is, what effect is the loss of these satellites going to have on my A65's accuracy if I do not switch to the RS125 antenna?

Thanks,

 

[Asureyez]

That question is something like "How High is Up?".

GPS gives great 500' radius accuracy from three Sats. With Differential signals you get down to 50'. If you get a 4th SAT accuracies can approach 10-12 feet!

If the SATS being decommissioned are the SATS you location depends on frequently, then your accuracy will vary depending on how many others SATS your antenna can see. Two SATS can give a fix but generally the equipment won't issue a fix on just two solutions.

Your experience will quickly tell you if you need to upgrade to a 125 ... I know I have one in my future.

 

[Presentation]

Where are / were PRN 122 and PRN 134?


If they are over, say, Hawaii then I don’t give a crap. If they were both over Wisconsin then it’s a big deal to me.

Does anyone know?

 

[MLauman]

They are both over the Pacific, however 122's coverage extends over much of the US. You can click on the map on these sites to see if your location is within the horizon...

PRN 122

PRN 134

 

[BocaDon]

Here is a reply that I received from Raymarine in answer to my questions;
1. What accuracy can I expect if I do not upgrade to the new antenna?
2. Will there eventually be a firmware or software fix?

"1. Raymarine is currently planning to post a FAQ advising customers of the RMS accuracy of a non-WAAS position FIX with the Raystar 12 GPS. I suspect that when this information is made available, most customers will find the difference in the WAAS and non-WAAS position FIXes to be minimal and well within their needs safely navigate their vessels.

2. The RS12 cannot be made to acquire the recently commissioned WAAS satellites through a software update."

 

[Asureyez]

Doug;

The Sat's on the horizion are exactly the ones that your GPS box uses to get your fix! Those out there just above your horizon are the ones you need and not one that could be overhead. :thumbsup:

Bet that was a news flash, eh!:grin: