It's worth noting that, when someone says that the get unreliable
readings near cliffs etc. the actual error is probably less than 50
metres. More than accurate enough for plotting which pond you recorded
at. Where I had problems with that was when trying to find a small
film canister cache hidden under a rock ledge 10 metres down an abseil
in our Morialta National Park. where I needed to go voer the cliff
within a couple of feet laterally of the correct location. BUT...as I
said, for plotting where you are in relation to a recording, I think
as long as you are getting a sat fix, then the error will be acceptable.
I've found that if the lock is lost, moving a few metres will
generally get it back. Also note that if you turn the GPS on outside
of about 100km of where you turned it off, it will take a slightly
longer time to fix you exact position.
With GPS averaging, it's interesting to see how inacurate they are. I
spent a few hours having coffee in Hahndorf, South Australia. By the
time I left, the GPS told me it had 'walked' about 150 metres.
Hope this helps you from agonising over an accuracy issue that isn't
really relevant.
John
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