First, cut off and discard both of the original connectors on the phone cable you
have, as shown in the example in Figure 17-3. Next, using the insulation stripping
blade on the crimping tool, remove the insulation from both ends of the cable. This
will expose a black, red, green, and yellow insulated wire.
In a normal phone cable the middle contacts use the red and green wires, carrying
the signal, and the same is true for the 1-Wire Weather Sensor??”the two middle
contacts are the signal connections. Because the 1-Wire system does not communicate
well using red and green wires which are next to each other we need to change
the connector wiring. To make this change we need to pick two nonadjacent wires??”
either black and green or red and yellow??”and have them connect to the middle two
contacts in the connectors at both ends of the cable (we do not need the other two
wires to connect to anything).
Figure 17-3
Modifying a standard
phone cable to work
with the weather
station
118 Project 17
I picked the red and yellow wires, cut off the green and black wires, inserted the red
and yellow wires into the same middle two contact pins in the connectors at each end,
and then crimped firmly. When you do this, be sure the contacts used for the red and
yellow wires are the same at each end. Reversing them will cause the connection to fail.
When the connectors are attached, you may repeat Step 1 to verify that the connections
are correct and the cable works.
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