If you want to "Extend the range" of a simple "Finger" type antenna (rod that sticks up) there is an interesting way... I use it, it works
go to http://amaturlogic.tv
Download and watch Episode 3 (I believe there are over 100 episodes, but Ep 3 is the one you want)
Now,, i did NOT modify the "Finger" (the Linksys antenna) so if I remove the juice can it's 100% origianl, but basically this is what you do.
Get a can of Grape Juice; Enjoy contents, Remove one end with can opener.
Drill a hole (George tells you where to drill) and insert a rubber grommet in hole.
Stick antenna "Finger" in hole, and point the open end toward the router's antenna (The park's router) seriously increases range.
Should work with the Wi-Fi Ranger, and if done the way I did, 100% reversible so you do not affect warranty on your electronics.