Hy, I use seaclear. It is a shareware programe that can be downloaded from The SPING Home Pageseaclear
/ You have to scan your paper chart and calibrate the immage . It takes some time but it is very good. And you have the paper charts
as a backup in case the technology lets you down. I have a small handheld garmin
gps that is connected to the laptop via the serial
port. It just lays inside near the window and has never let us down.
I use an old toshiba that runs perfectly on 12V dc.So as long the service battery
holds, we have a perfect immage.
The seaclear programe has also provisions for AIS
. But then you need an AIS
receiver connected in serie with the gps. The AIS information is integrated in ther mouving map.
This setup has given us great satisfaction.