Jack wrote:
Pardon a dumb question, unit doesn't the unit have to go to Cambridge
and be recertified to be good for conest and badge work? I'm in the
same boat and need the battery replaced. If i can do it myself, all the
better.

You're mixing up an S-NAV with a GPS-NAV. The GPS-NAV is an IGC
approved flight recorder, if the main portion of the case is opened,
Cambridge (or one of their agents) is required to inspect and reseal the
unit. However, the memory battery in the GPS-NAV can be replaced by the
end user, by removing the top antenna panel. Make sure you follow the
instructions very carefully, or your unit will be making the trip back
to Cambridge. Calibration is also required every 24 months, but any SSA
approved calibration lab can do that.

The S-NAV and L_NAV are flight computers, they have an end-user
replaceable battery for maintaining setup memory. You can just open up
the case, there is no mechanical or electrical sealing...

Marc