How long will the eTrex retain tracks, routes, and waypoints without power?
A. First, some background: The eMap and eTrex have a problem that other Garmin units do not. With other Garmin units, a backup battery powers both the local time-of-day clock and the waypoint memory. This battery is good for a couple of months, but for longer term storage you must keep batteries in the GPS. Thus, normally the real-time clock is valid. If the unit has been stored for several months without batteries, *all* user memory is lost, and the unit is forced to do an “autolocate” to figure out where it is – and it knows that because of the loss of memory. The eMap and eTrex use non-volatile memory for waypoints, so you can store them forever without batteries, and without losing waypoints or other info. So, people are more likely to do that. However, there is still a time-of-day clock that needs power. There is apparently a backup capacitor or battery that will power it for a short time (weeks?), but after that it stops. So, if an eMap/eTrex have been stored for several weeks wi
