Gees, I bet you had a dollar for every time a question gets asked about setting up a GPS!
My problem is I'm trying to format the SD card (in the memory card menu), but it wont let me - it says "turn off log first". How do I do this.

Also I'm trying to set the NMEA Items to SBN 1 Sec, but this isn't in the list - it has SBN Off. I click on this but nothing changes.

Also I set the Map Datum to Aust84, is this correct?

Thank you in advance for your generous patience with yet another techno inept windsurfer.

The reason it won't format the SD card is because it is logging data to it.
Soo.. you have to turn it off Memory card> log switch>off
Then format card
Then turn Memory card> log switch>on-fix

Nmea items click scroll down to SBN move joystick side ways to get to 1sec

Map datum WGS84 don't know why

Tom Chalko has his settings here http://mtbest.net/setting-up-navi-GT31.htm