Wireless bridge

Thu Jun 18 17:16:20 UTC 2009

> 
> 2.4 and 5GHz license-free Wifi is license free because the frequencies
> are shared with the ISM (Industrial/Scientific/Medical) services. In an
> industrial area, competing WiFi is the least of your worries. These
> frequencies are also used by industrial grade heating units. Got anyone
> in the neighbourhood running a large plastic shrink wrap machine, for
> example?

Good point.

> 
> You can't directly detect these other users with a Wifi transceiver.
> Depending on the nature of the interference you *might* be able to hear
> it directly on a scanner (if you can find one that covers those
> frequencies), but you really need a good spectrum analyzer to tell
> what's going on.

Check out http://www.ubnt.com/airview/ for a decent one. There is also 
wispy.