Modem to Modem Networking
Perhaps you've been in a situation where you wanted to network two computers that were in the same room and had modems but no network cards. This is a solution I worked up that lets you network two computers using phone cables, a 9 volt battery, a splitter, and a little help from the phone company.
First, you have to construct a component that is useful for several phone-based devices, like an acoustic coupler and a simple intercom system. This is what it looks like:
It's just a 9 volt battery connected into a phone cord. I made mine with about three feet of cord, but feel free to make yours longer if you want. Connect the battery terminals in series to one of the center two wires as shown. Don’t worry about any wires but the inner two. The battery supplies the power necessary for communication (usually it is supplied by the phone company). With that device in hand, plus the two computers you have (one configured to dial up to a server, and the other one configured to be a server), assemble them as depicted in this crudely drawn picture:
Notice that all phone cables should be plugged in at this point.
Now follow these steps to connect the two computers.
1. Have the client dial in to the server (you could have used any number as the dial-in #).
2. After the client has started dialing the phone number (you may want your modem speaker turned on to hear this), unplug the client from the y-splitter.
3. Use a cell phone or a friend to call your house and get the phone to ring a couple times. (this will make the server pick up the line)
4. Hang up the cell phone.
5. Reconnect the client to the y-splitter.
6. Unplug the y-splitter from the phone jack.
With luck, the two computers will now communicate along the custom powered phone line.
Courtesy of eric odegaard
6-20-2005
page 1 (modem to modem networking)