QUOTE (pbo @ Nov 19 2009, 05:52 AM)

back on-topic... I still don't know what "LO" means. It's bad enough that all RDS options are not explained in the manual at all.
'LO' is for local. In this mode, FM stations with a weaker signal are filtered out, letting only with the ones (generally local) with a strong signal through.
Depressing the AST button will enter the DX (long distance sort of thing) search mode. I haven't yet taken the time to properly try searching and storing stations in the DX mode, so, I can't tell you whether it's actually effective.