[talk-au] Cheap data logger

[John Smith]

Sorry for bringing up this thread, but just a sort of follow up.

The BT-757 is a very excellent GPS unit, has very good accuracy, when
compared to other traces and where the roads are current mapped, and I
would very quickly recommend this unit to everyone. As pointed out in
previous emails, the big down side is lack of memory, only 1MB, which
is only an issue if you use it as a stand alone unit. I filled it to
85% on a 9.5 hour trip, so if you are doing long trips it would
probably be best to log directly to a computer and not rely on the
onboard device memory.

The GT-730F/L on the other hand I wouldn't recommend to anyone when
doing OSM mapping, the accuracy just isn't good enough as it can be up
to 30-40m out, yet think it has only a few metres of inaccuracy. While
the potential memory storage is great, the device doesn't seem to log
as much data as it should.

I have both units set to log every 5 metres with no limit on other
options, and on the trip over to the Lismore area I have sections of
trip that wasn't recorded by the GT-730F/L but thankfully the BT-757
did log it all and with good accuracy and roads in the area have been
tweaked a little where they were badly mapped or mapped for landsat
etc or the existing map data was no longer accurate because of road
works.