i looked for another place to put this but as it isn't really a security q i couldn't find anywhere else. once i ge this solved i'll have lots of wireless security q's to ask so if you have advice on that too it would be great =)

i want to set up a wireless network which will go to about 400m in range using wireless network cards and custom made antenna's or "cantenna's". i've already done some research on the matter and i'm almost ready to get started but wanted some addition information....

my problem lies with the connection from my cantenna (pringles type) and then wireless card (laptop PCMCIA). i know i would use a pigtail for that connection but i might need a longer cable.

the cantenna would be on the roof (maybe 1m from roof tiles) and the pc which holds the PCMCIA card would be in the roof. this would mean i would need ~3m of cable and i am worried about losing signal strength. what are my options?