Hi Bruce, Interesting observations on PDAs and where to store files. I was aware that PocketTopo writes backup copies of the data file in use to the memory card, but I thought it cleaned these up when you saved the file (or maybe it is when you open a new file or close PocketTopo). I have never noticed my PDA memory cards littered with back-up files. Just seen one instance on the card when PocketTopo is running. So on that basis I assumed that the auto-backup feature will only save you if PocketTopo crashes or the PDA was destroyed (or battery ran flat) while in the middle of surveying. Once you finish and close the project (or switch to a different file in PocketTopo which I often do on a trip when working on large projects with several areas active) then you lose any auto-backup of the file you were last working on. If it is not on the memory card and the PDA then gets damaged (in transit in the cave rather than while in active use) then you would lose the data if only stored on the PDA internal memory.
I always take my cards out to copy data, but then my PDA is not sealed so it is not a problem. Instead I use the PDA inside a waterproof Aquapaq case which I can draw through but makes everything completely submersible (to 5m it is claimed, but mainly I just wash it in a stream if too muddy). I am working on a system to organise data for a larger cave, mixing historical data and recent data. I'll try to document it once I have determined that it really works. I have spent much more time working out how best to do things than actually drawing anything yet, as I want to be sure I am doing it right before spending the next few years drawing! Footleg -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.speleo.sk/pipermail/therion/attachments/20130615/42aa0bc3/attachment.html>
