Search for a Location
  Clear Recents
Metro
South West
Central West
North West
  Surf Cameras
  Safety Bay Camera
Metro
North
Mid North
Illawarra
South Coast
Metro
West Coast
East Coast
Brisbane
Far North
Central Coast
Sunshine Coast
Gold Coast
Hobart
West Coast
North Coast
East Coast
Recent
Western Australia
New South Wales
Victoria
South Australia
Queensland
Northern Territory
Tasmania
  My Favourites
  Reverse Arrows
General
Gps & Speed Sailing
Wave Sailing
Foiling
Gear Reviews
Lost & Found
Windsurfing WA
Windsurfing NSW
Windsurfing QLD
Windsurfing Victoria
Windsurfing SA
Windsurfing Tasmania
General
Gear Reviews
Foiling
Newbies / Tips & Tricks
Lost & Found
Western Australia
New South Wales
Queensland
Victoria
South Australia
Tasmania
General
Foiling
Board Talk & Reviews
Wing Foiling
All
Windsurfing
Kitesurfing
Surfing
Longboarding
Stand Up Paddle
Wing Foiling
Sailing
  Active Topics
  Subscribed Topics
  Rules & Guidelines
Login
Lost My Details!
Join! (Its Free)
  Search for a Location
  Clear Recents
Metro
South West
Central West
North West
Surf Cameras
Safety Bay Camera
Metro
North
Mid North
Illawarra
South Coast
Metro
West Coast
East Coast
Brisbane
Far North
Central Coast
Sunshine Coast
Gold Coast
Hobart
West Coast
North Coast
East Coast
Recent
Western Australia
New South Wales
Victoria
South Australia
Queensland
Northern Territory
Tasmania
  My Favourites
  Reverse Arrows
All
Windsurfing
Kitesurfing
Surfing
Longboarding
Stand Up Paddle
Wing Foiling
Sailing
Active Topics
Subscribed Topics
Forum Rules
Login
Lost My Details!
Join! (Its Free)

Forums > Windsurfing   Gps and Speed talk

Alphas and the GT-31

Reply
Created by sailquik > 9 months ago, 22 Nov 2008
sailquik
VIC, 6143 posts
22 Nov 2008 10:36PM
Thumbs Up

There is still a serious problem with the GT-31 and Alphas. I had two GT-31's on for testing today but I had to post my GT-11 speeds. The Alphas I got from the GT-31 were ridiculous and obviously erroneous when you look at the speed graph. One GPS said 27.980 and the other said 28.952!!!! I was pretty startled by the numbers at first glance but one look at the graph showed all sorts of strange bumps in the wrong places. I thought Tom had taken 'Smoothing' off in the newer GT-31 firmware but it certainly does not appear to be the case from these results. On the test firmware I tested with Tom recently with 'smoothing' OFF, the results were extremely good and very close to the GT-11 trackpoints with no strange bumps in the graph. These results done with the latest firmware were just plain wrong. If you are using a GT-31 for Alphas and that is all you have, the only thing I can suggest is that you use Doppler for the Alphas but that will be handicapping yourself with the current firmware. If you are serious about Alphas, please use a GT-11 and trackpoints, or even a Garmin for that.
The GT-11 gave me a new PB with 27.898 and a clean graph with no bumps like this:



The GT-31 gave me this with a very strange and false speed graph (shown here with the Doppler graph in green for comparison)



I will follow this issue up again with Tom and Locosys.

decrepit
WA, 12351 posts
23 Nov 2008 10:45PM
Thumbs Up

Thanks Andrew, there's obviously something weird going on there.
The filtering seems to want to cancel the min speed dip out.

BTW off topic, I was watching my gybes today, (not thinking about them, just watching what my feet do) and unexpectedly, my front foot goes in first.



Subscribe
Reply

Forums > Windsurfing   Gps and Speed talk


"Alphas and the GT-31" started by sailquik