re help with phone wire which ones are tip ring in article apr husc harvard edu mlevin husc harvard edu michael levin wrote i just bought a little gizmo that is supposed to be installed in series with the tip or ring lines of the phone wire which ones are those suppose i am holding a regular phone wire such that the little plastic tooth on the little plastic square thing with the naked lead ends that you plug into the phone is facing down and away from me which of the wires that i see is the tip and which is the ring please reply to mlevin husc harvard edu mike levin assuming you are refering to standard pots or ground start lines if you are looking at loop start lines under idle conditions the ring conductor is the one with approximately to vdc with respect to ground while the tip conductor is at or very near ground potential be sure to reference the telco ground when taking your measurements if you are dealing with ground start lines under idle conditions the ring conductor will be the one with approximately to vdc while the tip conductor would look like it s floating you may see some potential from line capacitance it will bleed off over time remember to use the telco ground as your reference when making measurements caprice sport coupe
