I had not tried this before, but I was picking up two weak signals on
vacation in Virginia and wanted to try to locate them. I downloaded a
1 mile X 1 mile local map from Route 66 and loaded it in. Then I
connected my TripNav GPS and set two waypoints. Bingo! There were the
sites clearly marked!
I had been very curious about how this works, I now see that the two
waypoints set the internal scale for the map, which makes it possible
to locate wi-fi sites. I still don't know how it can figure out
location from just one angle, but it seems to work.