====== Model 137 Aircraft Hygrometer ======
  * Description: Dew Point Hygrometer
  * Manufacturer: EdgeTech
  * Model: 137 -A3
  * Serial Number: 36278

===== Configuration =====
==== April 21, 2010 ====
The temperature range configuration was changed from -60 C - 40 C, to -70 C to -30 C.  The serial output frequency was changed from 5 seconds to 1 second.

===== Specifications =====
  * Dew/Frost Point Range
    *−50 to +90 °C

  * Dew/Frost Point Accuracy
    *±0.20 °C nominal

  * Depression
    *65°C,nominal

  * Slew Rate
    *1.5°C/second max, above 0°C

  * Repeatability
    *± 0.05°C

  * Precision
    *0.1 °C

  * Sample Flow Rate
    *0.25 - 2.5 liters/minute

  * Operating Temperature
    *Control Unit: 0 to + 50°C
    *Sensor: 50 to +100°C

  * Power Requirements 
    *90 to 240 VAC, 50 - 60Hz 
    *75 watts Maximum



===== Pictures =====
Picture of Control Unit Side

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Control Unit Back

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Control Unit Face

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Sensor Head

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Data Cable

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Sensor Element

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