I can then encrypt the database on the 256MB card. But here is the
catch, the Airmap has known issues with some brands of SD cards and
they recommend using SanDisk brand. The SD card I bought was not
SanDisk, but seems to work just fine. I will try it tonight after
calling their tech support about my SD card brand.

Yes, that's a problem. However, if your unit has read the card
succesfully already, it will in all likelyhood work with the Jepp data on
it, too.

I called Lowrance last night and they told me as long as I have the latest
FW version on the Airmap the brand of SD card will not matter.
Additionally, as you said, they told me if it already worked once with the
land maps it will not be a problem when I put the aviation maps on it.

So I got the upgrade on the SD chip and put my land maps on there too... I
am pleased to report it all works without any problem!

Thanks for the tip on the free database update. I still could not find it
in the manual. shrug oh well...

--
Mike Flyin'8
PP-ASEL
Temecula, CA
http://flying.4alexanders.com