My hub is sitting vertical in the white box under two Skys. The Sky with black tape RSSI is -1 the red tape is -16. I am in southern hemisphere so my solar panels face north.
View of the Hub from the south side.
Then I have a Sky over 2 miles away to the north reading RSSI -85.
When the Sky is over 7 miles from the hub I have used a parabolic antenna to pick up a good signal. All displayed and described here:
It would be simple to create your own parabolic reflector out of any metal mesh. People extend their wifi using a tin can cut open so experimenting with anything simple might return results. The RSSI value might only update at your last ‘status’ time.
cheers Ian 