Once you have determined that you have temperature, wind speed, and direction
measurements displaying on your PC, as shown in Figure 17-2, you??™re ready to
prepare cabling and install the measuring unit where it will work best.
Figure 17-1
Weather station
software configuration
for the AAG instrument
Figure 17-2
The AAG weather
station software
showing data from the
measuring unit
PC Weather Station 117
Step 2: Prepare the Cable Connections
Because the AAG weather station uses standard phone cable and connectors between
the sensor and PC, the signals are such that they can easily get lost in the cable,
especially a long (25 feet or more) cable. If you are going to place the sensor unit on a
16-foot-tall pole, or your roof, the cable length needed will probably be at least 25 feet.
To avoid the loss of signal (which appears as ???no device detected??? in the test programs)
you need to modify the standard phone cable so it can pass the data signals
over a long distance. The trick is that normal phone cables use two wires parallel to
each other, which creates a lot of capacitance and diminishes that sensor data signal.
To avoid this capacitance, we need to use nonadjacent wires.
The necessary cable modification consists of removing the original connectors
from a premade cable and reattaching connectors using different internal wires, or
making your own special cable. It??™s very easy to do this modification using a $6??“10
RJ-11 connector crimping tool and a pair of RJ-11 modular plugs.
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