In article ,
Marc Ramsey wrote:

5Z wrote:
I suspect you send it back and have it resealed. Sounds like you broke
the tamper seal in the device.

It *may* still be usable as an insecure FR, but forget badges or
records.

Tom is correct, you broke the electronic seal. It needs to go back to
the factory or an authorized agent. Send an email to LX Navigation to
find out what your options are...

Marc

The 9v NiCd was no longer holding a charge, so the only way the LX-20
would operate was on external power. Upon investigation I see that when
I opened the case to also replace the original nearly 10 year old
lithium watch battery which supplies power to save settings (name,
glider, units, etc), a micro switch opened.

Whether you're replacing the lithium battery because it is old or
because it has died, you still have to open the case, which opens the
micro switch and invalidates the security code. Actually, it's probably
better that this happened now, instead of in flight, in the middle of
the soaring season. I still have time to get this resolved. The 9v and
the lithium battery lasted for nearly 10 years, so they were due for
replacement. What's the reasoning behind hiding the LX-20 lithium
battery such that it can't be replaced without opening the micro switch?

I hear that there's a DOS application from Filser which resets the
security code, and that this is an issue for a number of secure flight
recorders. That is, there are other units which have a small battery
that when removed for replacement, cause the same problem. How do other
manufacturers handle this?

I note that my home central heating/cooling display uses a pair of
lithiums in parallel, so you can replace them one at a time without
losing the stored program.

Ken