I'm curious how long the battery stays charged on your handheld VHF's when not in use? I've got a Garmin handheld which, after it was fully charged, lost its charge within a week or 2 when it wasn't even in use (just sitting in the "off" position). This happened when the radio was still new. Garmin graciously sent me a new battery, but the new one isn't much better. I know you're not supposed to re-charge until the batteries are fairly low, and I've been good about doing that. What kind of battery charge-time is normal when a VHF sits un-used? Thanks!