For the 2nd or 3rd time, our GPS has just not recorded any data from a session.

Kellie sailed for 2-3hrs this afternoon, and when I popped the card into the computer, it was blank.

When I turned on the GPS (GT-11) it said Card Found and New File, and when I put it into the computer, the card had a new file on it.

I went so far as to connect the device by USB and tried to load data via Navilink. Instead of today's session, I got an old session from Jan 19, which also didn't record on the day. It seems that the device chose to record that session onto the internal memory of the GT-11 instead of the card.

Anyway, if there is more than one session on the internal memory, I can't access it.

I have backed up the internal memory to disk via Navilink, but the backup file can't be read by Realspeed.

Help!

What brand card is it? Some cards need 3.3v to work, I think the NAVI only gives out 2.7V or so.

I've now done that, but still can't read the previous file.

I have a recovered .SBP file that is 871KB but when I load it into RealSpeed it shows only three points, dated 25/4/2018!

If someone thinks they can recover this data, please let me know and I will send you the file.

[Added later: I exported the file to a gpx file with Realspeed and loaded it up in Google Earth. The start location for the track is spot on, Caloundra, but then the next location is on the other side of the world off the coast of West Africa! That's one hell of a reach! Anyway, the fact that there is a valid starting point gives me some hope...]

I have spent several hours looking at this now.

I have verified that I have a .BIN file containing tracks from the 26th of January (and before.)

I have been able to load the tracks into GPSResults, and export them as .gpx files, but the dates are all munged up. Although I can see in the .BIN file (using a binary editor) that the correct date and time are stored, when the file is loaded into another program like GPSResults, it gets the coordinates right, but the date and time info is all messed up.

Something must be wrong with the format of the data file or something.

I can see the data there, so I am still determined to work it out.

Any idea why the date format might not be correct? Or any input on what it actually should look like?

I'd really appreciate it if someone running firmware 1.61 could dump off a .BIN file for me to look at.

Hi Dylan,
Firmware V1.61 doesn't narrow it down enough. You can look in the settings menu to see what version is loaded. the latest one is '1115'.

I can't figure out why you have a file with the 'bin' extension. Yo must have a quite old version of the GT-11 firmware. The current firmware produces file with .sbn extension (saved directly to the card) or NMEA if you have it set to that. The data logger saves files in the .sbp format.

If you turn the GPS on and go to the data logger screen you will find a menu item 'save to card'. That will dump the sbp file on the SD card.

If you were using older firmware and have a file with a .bin extension, RealSpeed should be able to read it. If it can't, send the file to Mal Wright (intellimass.com/) and he might be able to work out why.

If you follow the instructions at www.mtbest.net/setting-up-navi-GT-11.htm to set up your GT-11 you should be right. EXCEPT, I recommend you set the LOG switch to 'ON'. (NOT "ON-FIX' as recommended in the set up guide. There have been some problems with this setting).