No PICs here (yet). I'd be interested in hearing from people who have experience with 802.11b networking over significant distances. Offlist if too OT but I suspect many would be interested to know what has been achieved. Any comments on specific points covered below would be welcome. This is not the best forum for vast discussions on this topic - whether we should take this offlist depends on response and general interest. I'm about to venture into playing with 802.11b wireless networking. A major longer term aim is establishing reasonably long distance 1 to 10 Mbit communications links. Initially the aim is to get a feel for what's involved by establishing successively longer medium range links (A = 400 metres / not quite LOS, B = 3 km / will be LOS when I find a high point, C = 6 km / will be LOS when I climb that pine tree at the far end) and then work up to getting as much range as possible. One longer term aim is to extend one leg to a city H about 130 km / 80 miles South of here using as many hops as it takes and as few as possible. I have access to one high point D on the South side of my city with a clear line of sight over water to a higher point E about 30 km / 20 miles South. From there it's 85 km to the final destination H with some variably hilly country in between so I am going to have to find some suitably interested farmers along the way :-). From my location to H (on the water) is only about 11 km but high ground between means there will; need to be at least one intermediate point. (One PICLister mentioned achieving 46 miles (AFAIR) on a single hop but this was with powers well above the NZ legal limit.) Our regulations limit effective power to 36 dBi or 10 milliwatts into a 26 dBi parabolic (about 0.8 metre diameter). There is no restriction on receiver antenna gain and I will look at larger dishes for the relay point although maximum size is limited by aesthetics and cost. Surplus satellite TV dishes from "the early days" should be available at reasonable cost. This is essentially a "hobby" venture at this stage although something commercial may grow from it in due course. I'm keen to spend as little as reasonable on hardware at this stage as long as labour requirements are not vast as a consequence. A tour of some of the vast amount of web resource on 802.11 suggests that extremely useful aerials can be made with very little work (eg coffee can and an N connector gives a 16 dBI waveguide antenna for 10 minutes work after you've spent N days getting the first one right). I have my doubts about the Pringles Can designs. Driving a surplus 65 cm parabolic antenna should allow gains in the 22 - 28 dBi range. (There are some VERY poor "designs" published as well). I'm considering with DLink USB cards to start as these are available locally, are the lowest cost in this market and have RF specs (TX level, RX sensitivity) similar to most others generally available. The USB versions do not have an external aerial connector but there are numerous "how to" pages on adding one to various cards. (Technically this is a trivial task but in practice knowing that many people have modified 2.4 GHz gear like this is comforting.). I favour USB cards initially due to flexibility - hey can be operated in desktop or laptops and if desired may be mounted near the aerial with feed by USB cable rather than using longer potentially lossy coax runs. There is a potential loss in throughput due to the USB interface being specd somewhat below 11 Mbps but this loss of throughput is irrelevant during initial investigations. . I'm probably not buying an access point to start as I can ascertain the practicality of longer ranges without one. Various open source solutions are becoming available. Thoughts ??? Russell McMahon -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu