I have installed a Garmin 168 chartplotter/sounder. The unit has 2.5 MB of
internal chart storage memory. My question is: How much coverage area of
NOAA navigation chart data, from the BlueChart CD-ROM, can be stored at one
time? My area of interest is San Francisco Bay, Suisun Bay, and the
Sacramento and San Joaquin rivers. It takes somewhere around 20 to 25 paper
charts to cover this area. To plan a route of say, 30 miles, from Benecia
to Alameda, would the Garmin 168 be able to hold the required coverage area
with a single download, or would this route require repeated downloads to
map the whole area? Having to do several downloads during the trip would
not be practical, since I don't have a portable computer.
I notice that the more expensive Garmin units use plug-in memory chips with
capacities of as much as 128 MB, and my concern is that the 2.5 MB of memory
in my 168 seems awfully small compared to the 128 MB chip.