From the Club 100 support files (www.club100.org)...

PHONE MODEM CABLE WIRING

This is the view of the back of the connector that plugs into the phone port 
on a Model 100, 102 or 200--where you re-solder the wires after ripping them 
out of their sockets!!  Obviously, this is the weak point in the system.  
Note: You can actually swap the red and green--it will work either way. 

             o           o---green

     red---o       o       o

             o           o

                   o

When you look at the end of the RJ-11 plug (the end that goes into the wall), 
the order of colors are: [Yellow] [Green] [Red] [Blue] 

The "old style" phone/modem cable once offered by Tandy/Radio Shack has two 
separate wires coming off the Model "T" end plug.  The gray lead went to the 
phone jack in the wall and the beige went to a separate phone.  Here is how it 
is wired. 

Pin 7 is green in beige,
Pin 1 is green in grey,
Pin 3 is both reds (common).
7 and 3 are the leads to connect (1 and 8 are for a separate phone).

The Club 100 phone/modem cable has only one lead.  It is used to connect to a 
phone line, only.  If you also want to use a separate phone, simply go out and 
purchase a RJ11 "Y" adaptor for the phones wall jack -- plug the phone/modem 
cable into one side and the separate phone into the other side.  This set up 
will work the same way as the 2-wire original phone/modem cable. 

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