I don't actually know how to do this. It was such a nightmare setting up my router (see past posts) that I don't want to fiddle with it. If it is something I can do on my Mac, then directions, please.
I was afraid of that. Without knowing how your router is set up or whether or not it creates a blended network or separate networks for each band I wouldn't know where to begin to advise you.
Just keeping Bluetooth turned off on your old Mac is probably your best option.
