Dag, Here are some thoughts
It all depends on what you want to do. Putting the ACII on an ethernet connection is helpful when you want the computer running aquanotes to be located at some distance from the tank. If you don't need the distance then you can stop here and just hook the computer via the serial interface to the ACII.
If you have one computer or need to locate it far from the tank, you need some way to connect the ACII to the computer at a distance. What some people do is use their existing ethernet network as a means to hook the two together. Your existing ethernet network can be as simple as the ethernet wire from your computer to your router or the wireless ethernet link from your computer to wireles router. In theory all you are doing is putting the ACII into the ethernet network so the aquanotes software running on your computer can find it.
But, an ethernet wire is still a wire that will need to run from the ACII to your router. If this is ok, then you just need a serial to ethernet adapter This device has a serial connection on one end that plugs into the ACII and the other end has a cat5 ethernet plug connection that your ethernet cable plugs into and then runs to the same kind of plug on your router. Tonga_Man has some recommendations above in this thread on the type of adpater to get and the configuration of the software that comes with it.
If you need wireless, then you need to get an ethernet to wireless bridge like the Dlink unit that Tonga_man and I discussed above. This unit plugs into the ethernet cable (a short 6 inch cable will do) going to the serial to ethernet adapter. So it looks like this - ACII plugs into the serial to ethernet adapter, serial to ethernet adapter plugs into ethernet to wireless bridge. From this point, if you have a wireless router, the ACII can communicate with the router wirelessly. You dont need a wire or computer anywhere near the tank. Once the ACII is linked to your wireless router, any computer you have that is hooked up either by wire or wirelessly to the router will be able to run aquanotes and communicate with the ACII
. So some folks have converted the
You may want a dedicated computer to run aquanotes so it is always available