How do I know if a reading is a spike in Realspeed

For a spike Andrew, on the graph section, you will see a spike in speed change, something like, you will go from say 20 knot speed and the next reading 1second later will be much higher, with a rapid drop off back to normal speed shortly after.
tab the division 2 second tab which will highlight the section you scored highest speed on the left panel showing your tracks, correspondingly it will show up in the bottom right numerical recoded panel (above the graph) you can the scroll down though the numbers to see if you had a legitimate ramp speed up and down for that period, compare this too the rest of your ramp speeds to gauge if you had a spike.
Hope this helps (and I got it right)

Finally if you haven't already joined a GTC team over there, do so and you will have that much more fun. Its free and always looking for new members.
Here is the link
www.seabreeze.com.au/forums/topic.asp?TOPIC_ID=28011
Here is the link for the top man driving the recruiting
www.seabreeze.com.au/forums/topic.asp?TOPIC_ID=45055
Mineral

thanks sailquik & mineral1. the "ramp-up" and "ramp-down" seem smooth enough, similar to most other runs that day.

sailquik, i have sent you the gpx file 'cause i would appreciate a 2nd opinion.

by the way i use a gt-11.

cheers,

andrew

yeah, i know. i have been doing that but must have changed a seting by mistake because lately this has not been saving an sbn file (just realised this last sail and fixed up the settings). i do get an "sbp" file when i use navilink to get data from gps though (this is the file i sent you, sailquik)