|Hugh Blemings's Blog|
Tue, 04 Oct 2005
About a year ago we bought a 16 acre block of land in Carwoola, about 10 minutes from Queanbeyan. Lu and I have long liked the idea of living out of town a bit and having space set up so that we can invite friends, family, colleagues etc. out to stay in a guest house. Idea is to set it up sorta like a retreat so folk can come and stay and have time out, watch the world go by and relax and, in the case of many of the people I know, have decent bandwidth as well so that patch can still be submitted :)
Friends of ours live about 400m away and we've got pretty clear line of site to their place. As of about six months ago they also got ADSL - the RIM at the end of the road was upgraded. I gave Chris a hand with getting it set up and we installed a Linksys ADSL Modem/Router to feed the local network.
A bit of browsing of their website and a few emails back and forth with the guys at Freenet Antennas confirmed my thoughts that a link between the two sites would be a no-brainer.
At Chris' end there's a Minitar access point in one of Freenets' Rootenna enclosures that has space for the AP at the back and a 14dBi directional antenna at the front. The advantage here being that you have a very short run for RF (20cm) as the AP is right up next to the antenna. Instead you send ethernet and power up to the far end which you can do over a few tens of metres without ado, unlike 2.4GHz RF. Took some photos of all this starting here.
Network wise, the AP at Chris' end plugs into a small DMZ so it can see the ADSL connection, but not the home network.
The other end of the link uses a 14dBi yagi also from Freenet with a short length of coax to plug into the back of a second Minitar AP. The APs are configured in point to point mode. For now it's (obviously) a portable setup - AP runs off a 12V Gel cel and ethernet goes directly into back of my Thinkpad. Some shots of the setup used for the "First Post" entry are here.
On the basis of the tests on the weekend it works quite nicely, indeed we were able to bring the link up by pointing the yagi away from the AP and using a signal reflected off the side of the hill. On rough calculations the antenna gain available should be good for a couple of km - I took the view that I'd rather have the extra gain to obviate any potential problems with rain and/or trees in the path
Next steps are to get the remote end a bit better integrated (portable mast of some kind, cigarette lighter adapter for AP etc.) and then we'll be set for next time we go camping out there.
In the meantime, if you fancy doing your next commit from among the gum trees get in touch :)