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The temperature array consists of three orthogonal 1 meter axes of PVC pipe, suspended raised 1 meter off the ground.  Running along each axis is a thermistor-thermistor pair, forming a voltage divider.  For each pair, one of the thermistors is mounted at the vertex of the three axes (circled in blue above), and the other is at the end of each the axis (circled in red above).  The voltage between the two thermistors (the output voltage of the voltage divider) is read out.  The supply voltages are provided and the output voltages are measured from an electronics control box at the foot of the temperature array (boxed in green above).  Together, these three axes provide measurements of thermal variations with mK prevision. 

An external control computer directs the Arduino ADU that provides the source voltage and digitizes the output voltage at 1kHz.   

See the pages below for further details.  

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