just connect any two of line, pickup the handset, if you can get dia tone, that should be right one.
-winger1234(ben);
2002-1-16(#336642@0)
You can try the following approach: Select any two of the four wires, connect(with your hands)to the plug of your telephone,the pair which makes the a dial tone is the pair your're looking for. Ignore the other two wire.
-longshot(叶子);
2002-1-16(#336651@0)
Why not buy a 3 way splitter?
-guest3(guest);
2002-1-16(#336800@0)