Jump to content

Bt-338 And Waas (enabled?)


Recommended Posts

I just got my BT-338 back from GlobalSat and It was "updated" although I am still not receiving WAAS satellites. Any idea how I can verify if I am getting/not getting them? I used my trusty Garmin Vista and it picked up one so I know there out there :-) Any help would be appreciated. Just trying to verify it has been updated.

Link to comment

I just got my BT-338 back from GlobalSat and It was "updated" although I am still not receiving WAAS satellites. Any idea how I can verify if I am getting/not getting them? I used my trusty Garmin Vista and it picked up one so I know there out there :-) Any help would be appreciated. Just trying to verify it has been updated.

Look for satellite numbers 33 and 35, those are the WAAS satellite numbers. However, 35 is not being picked up by a lot of people as it is being moved to a new western position. However, I get 33 almost all the time.

 

Funny thing about satellite 35, it shows up on my Magellan but not on the BT-338 and other users with SirfIII chip garmins seem to have the same issue.

 

(edited to add) The other way to know, is that when the BT-338 is using WAAS programs like cachemate will display DGPS fix.

 

JDandDD

Edited by JDandDD
Link to comment

Look for satellite numbers 33 and 35, those are the WAAS satellite numbers. However, 35 is not being picked up by a lot of people as it is being moved to a new western position. However, I get 33 almost all the time.

 

Funny thing about satellite 35, it shows up on my Magellan but not on the BT-338 and other users with SirfIII chip garmins seem to have the same issue.

The satellite with Garmin #33, PRN #120, is an EGNOS bird, AOR-E, and should not be used by receivers in the US and Canada although it is visible in the eastern parts of those countries.

 

The current WAAS satellites and their Garmin numbers are: #35 (currently moving but still giving correction data), #47 (over the Pacific and giving correction & ranging data), #38 (new Anik bird at W107 giving correction data but still in test phase), and #48 (Galaxy15 at W133 giving correction & ranging data but still in test phase). Add 87 to the Garmin numbers to get the PRNs.

Link to comment

I sent it in to be updated, but when I got it back its not picking up any WAAS sats. The only ones I am getting are 21, 18, 15, 09, 26, 29, 22, 03 and 07. It also has 14,10 and 6 but no lock on them. None of these are WAAS are they? if not how do I enable WAAS? anyone used the SiRFDemo to activate WAAS?

Link to comment

Another way of telling is by the signal stream using the GPSinfo software on the setup tab select the WAAS checkbox. In the NMEA sentences look for the line below.

 

$GPGGA,170834,4124.8963,N,08151.6838,W,2,05,1.5,280.2,M,-34.0,M,,,*75

 

If you see a 2 in the bold spot you've got a DGPS or WAAS fix if it's 1 then it's ordinary GPS fix.

 

Further infomation from: http://home.pacific.net.au/~gnb/gps/nmea.html#gpgga

Link to comment
CacheNav displays "DGPS" in the fix indicator when I've got a WAAS lock on my BT-338. I had to have it updated as well, but since then I've been able to recieve WAAS corrections. Freejam is also correct about the 2s showing up instead of 1s in the NMEA string. You can use the GPS Info program that came with the receiver to read the NMEA sentences when the receiver is on and has a fix.
Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...