I'm a bit unsure whats going on when I see the data in reelspeed from my foretrex 101. There's a few issues someone may already have corrected.

1) The unit is set to 2 seconds for recording and alot of the points are 2 sec apart however theres plenty that are anything from 4 to say 80 seconds, this is most often when on the beach with little movement but also occurs when underway.

2) Todays sail had alot of red lines show up on realspeed indicating I'd been timewarping around. Could this be due to playing in the waves and being frequently under water? I put the aquapack in my boardies pocket.

3) If I download data direct from Realspeed I get weird times for the trackpoints eg for today it showed my times as 11th Nov 0100 etc. Times are consecutive but wrong. If I download through another program 'EasyGPS' and save as a gpx file the track looks the same but the times are now correct.

Any Ideas

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sailpilot said...

I'm a bit unsure whats going on when I see the data in reelspeed from my foretrex 101. There's a few issues someone may already have corrected.

1) The unit is set to 2 seconds for recording and alot of the points are 2 sec apart however theres plenty that are anything from 4 to say 80 seconds, this is most often when on the beach with little movement but also occurs when underway.

2) Todays sail had alot of red lines show up on realspeed indicating I'd been timewarping around. Could this be due to playing in the waves and being frequently under water? I put the aquapack in my boardies pocket. Herin probably lies most of your problem, GPS must have a clear vision of sky else it drops in and out

3) If I download data direct from Realspeed I get weird times for the trackpoints eg for today it showed my times as 11th Nov 0100 etc. Times are consecutive but wrong. If I download through another program 'EasyGPS' and save as a gpx file the track looks the same but the times are now correct.

Any Ideas

And the data you get will be suspect as well.

The Foretrex has a neat feature (well garmin thought so) called track smoothing.

In the position you put it , it will always be blocked from at least half the satellites (by your body) and the ones you see will be constantly changing as your body direction changes.

When the gps locks on new satellites it can get a different position from it's calculations , rather than jump from one position to the new one it will blend the trackpoints producing a smooth track that looks normal but may be 5 knots faster than what you actually did.

Upper arm is best.

Thanks for that, I will avoid the pocket stowage from now. I've tried the arm but didn't actually like it being there and I don't bother looking at it on the run. I think I saw a thread once where someone had it above the boom on the mast?

www.seabreeze.com.au/forums/topic.asp?TOPIC_ID=41592&SearchTerms=paqua