Hi Chris,

Considering "because".
I apologise in clutterring up your thread, The figure of 5000 feet is my conversion of the 1.5Km published by maxstream, not my own data.

a mesh I know works easily within and outside buldings of differrent materials some of which are large steel clad industrial units, the site extremes are approx 1500 feet x 2500 feet, I have no data for the maximum distance between any two modules.

I did not buy a development board, I took a punt on them and imported a part tube from Digikey USA, I then designed a small dev board of my own and panelised it into an existing board run.

Ron Marcus has suggested radiometrix as well, Radiometrix is an RF guy he writes quality readable authorative articles over here in the UK on RF, hats off.
I really am wishing now I had not put my oar into this thread without properly reading the title.

Duncan