[sclug] Long distance Wifi

[Peter Brewer]

Tom, Ed and Raz

Thanks for the input.  Will definitely give this a go but will have to 
wait for our friends in the valley to get back from their holidays 
first!  In the mean time does anyone have any links to idiot guides on 
building antenna?  This will have to be a budget project as gadgets (and 
mortgages) make me a poor man. :-(

Cheers

Pete



Tom wrote:

> Pete,
>
> This is totally possible. I have put a link like this together from 
> two LinkSys WRT54G's and homemade antenna's and recieved 90% signal 
> strength over almost 1Km from tree top to tree top over a motorway and 
> a railway track from a house to an alotment
>
>
>> First, is this actually possible?
>
> Yes
>
>> How far can these antenna work?
>
> The pair of fat tin cans I used at each end theoretically should work 
> over 8km but as most of my implementations have been in urban 
> environments, getting line of sight has prevented testing it that far 
> yet. Ping times about 6ms from router to router.
> I have experimented with using old satelite dish's (reclaimed from 
> skips) to focus the beam. I have seen plently of tests showing this 
> can increase the distance four times or more if aimed preciecesly and 
> mounted well. These are a little less discreate though.
>
>> Our closest friends are about 1km away in direct line of sight.
>> Second, is it legal?  How do people like BT view sharing a broadband 
>> line like this?
>
> In my mind 2.4Ghz is a public spectrum and any limits on paper are 
> there to prevent anyone broadcasting at a level that would reduce 
> other peoples access to the resource. Although this would happen if 
> you suped up a access point in a busy area, using directional 
> antenna's is another matter. They only increase the signal in one 
> direction and reduce it in others. As long as you aren't pointing it 
> at anyone else's property without permission then they amount of 
> "noise" your neighbours will get will be LESS when you use a 
> directional antennna than if you didn't. Although this is not how the 
> regulation is worded as such I strongly doubt anything would come of 
> it unless you were effecting anyone elses equipment, and even then, I 
> would encourage you to use contact details as the name of the access 
> point so anyone wishing to complain about it could contact you 
> directly instead of haveing to use the regulator to come and track it 
> down.
>
> I'm sure other members of the group have sent you suggestions as well 
> but if there is anything else you want to know feel free to ask.
>
> Tom