Hoping this is an easy remedy. Now that I'm using a GT31 I can't seem to decipher the 1 hour speed in Realspeed. It has a ridiculously large speed, something like 8229...!!!
Am I missing something simple here?

usually takes an "hour" to work out

Select to expand quote

sick_em_rex said...

Hoping this is an easy remedy. Now that I'm using a GT31 I can't seem to decipher the 1 hour speed in Realspeed. It has a ridiculously large speed, something like 8229...!!!
Am I missing something simple here?

Can you tell us which version of RealRpeed you are using and which file type you are using.(.sbn or .sbp)

Also, the settings in your .rsp file for the 1 hour.

Sounds very strange, are the other divisions OK?
Are you using doppler??? That should eliminate any strange "spike".

I think most of us are using doppler for every division apart from alpha, where track points is more accurate.

Select to expand quote

decrepit said...

Sounds very strange, are the other divisions OK?
Are you using doppler??? That should eliminate any strange "spike".

I think most of us are using doppler for every division apart from alpha, where track points is more accurate.

Shouldn't i be using doppler for alpha!!!? I've just always udes doppler for everything because i thought it was more accurate...

Bubs

Bub's, seems doppler reduces alpha's too much, and trackpoints are more accurate, but there is the possibility of it including a false spike.
You need to check the track to see that it's the proper "U" shape. If still not sure you can check the data and make sure there's no interval greater than 1sec, or compare it with the doppler result, and make sure they're both using the same track.

Select to expand quote

decrepit said...

Bub's, seems doppler reduces alpha's too much, and trackpoints are more accurate, but there is the possibility of it including a false spike.
You need to check the track to see that it's the proper "U" shape. If still not sure you can check the data and make sure there's no interval greater than 1sec, or compare it with the doppler result, and make sure they're both using the same track.

Hmmm, following topic but off sik em's original point I have just looked at my pb alpha now I have reset my alpha from doppler to Trackpoint. This increases my pb by .6 knots. I shall now leave Realspeed Alpha division on trackpoint and hope to get a good alpha soon ( if we get some wind).

Back on topic, did you resolve your 8ooo+ knot issue, Sik em?

Set it up like this:





The problem is probably the "Strict (no invalids)" box.

Ok, the version of Realspeed is an update I got from Elmo and it's dated Novemebr 2007.
I am using sbn files.
All other files as far as I can tell are fine, although I do think I'm using doppler to do my alphas so I'll check that.
Nebs I went in a changed those settings as per your screen shot and from what I can tell it has made no difference. Andrew I presume that's what you were alluding to when asking of my settings also...?
I have looked at the time I spent on the water and from what I can see I was definately sailing for over an hour so that shouldn't be an issue.

Thanks sick-em-rex, that was what I was asking except check if you have version 1.925. But it sounds like everything is set up correctly. Could you send the file to me to have a play with please to see what I can find. I will PM you.

On its way mate. Thanks

The issue with Alphas is that in the GT-11 the Doppler speeds in alphas often get some strange bumps in the sharp turns. The trackpoint speeds do not seem to have this problem but you need to visually asses the speed graph to double check there are no stange bumps in the speed. It should be a fairly even V or U shape. If it has a slight W shape in it it is highly suspect.

This is why we are advising to use only the trackpoints for the Alphas in the GT-11

To compound the problem, the GT-31 was originally displaying these strange speed artifacts on BOTH the Trackpoints and the Doppler.
An updated firmware was produced that turned off some internal 'smoothing' function in the Chip and that seems to have eliminated the issue altogether with both the Trackpoints and Doppler looking exactly as they should. It seems that this has overcome the problem but more testing side by side with a GT-11 is needed to see if the results are compatible for the rankings.
The best thing to do at the moment is to use the GT-11 on trackpoint settings for Alphas but if you only have a GT-31 make sure you have the updated firmware installed and use the Doppler results from this unit.

Sent an email Sick'em.
I got the exactly same result in RealSpeed v1.925 as in GPS-Results and it look to be as expected for normal result.
I have sent you my .rsp file and screen shots of my settings so you can compare yours. It could be that the error filters in 'options' are not set to filter out the spike in the middle of the run.

I tried an upgrade of the installation and it seems to have done the trick. Maybe I did have a slightly older version afterall.
Thanks for all your help Sailquick

Sorry to hear you were not the first sail craft to break the 8000kt barrier Sik em. Guess the kites will be there before us