SGP/SIRS/E19 - Intermittent bad data

From 9/21 to 10/10 0015GMT the DSH (down_short_hemisp) values were intermittently missing 
while simultaneously ULH (up_long_hemisp) and DLHS (down_long_hemisp_shaded) values were 
much lower than possible values.  This problem was attributed to an unidentified mux 
related problem. Although the problem did not recur after 10/10, the mux was replaced on 11/03.

The problem was intermittent, occurring for significant parts of each day. The QC flags 
appear to adequately flag bad data.

Use the QC flags to filter for good data.

• Instantaneous Upwelling Pyrgeometer Case Thermistor Resistance, Pyrgeometer(inst_up_long_case_resist)
• Instantaneous Downwelling Hemispheric Shortwave, Pyranometer Thermopile Voltage(inst_global)
• Instantaneous downwelling pyrgeometer dome thermistor resistance, shaded
  pyrgeometer(inst_down_long_shaded_dome_resist)
• Instantaneous downwelling pyrgeometer thermopile voltage, shaded pyrgeometer(inst_down_long_hemisp_shaded_tp)
• Instantaneous Upwelling Pyrgeometer Dome Thermistor Resistance Pyrgeometer(inst_up_long_dome_resist)
• Instantaneous Upwelling Pyrgeometer Thermopile Pyrgeometer(inst_up_long_hemisp_tp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Shaded
  Pyrgeometer(inst_down_long_shaded_case_resist)

• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Minima(down_short_hemisp_min)
• Downwelling longwave hemispheric irradiance, shaded pyrgeometer(down_long_hemisp_shaded)
• Instantaneous downwelling pyrgeometer case thermistor temperature, shaded
  pyrgeometer(inst_down_long_shaded_case_temp)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Shaded
  Pyrgeometer(inst_down_long_shaded_dome_temp)
• Downwelling longwave hemispheric irradiance, shaded pyrgeometer, standard
  deviation(down_long_hemisp_shaded_std)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer, Maxima(down_long_hemisp_shaded_max)
• Instantaneous Dome Temperature(inst_up_long_dome_temp)
• Downwelling longwave hemispheric net infrared(down_long_netir)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer, Minima(down_long_hemisp_shaded_min)
• Upwelling Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Instantaneous Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_netir)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
  Standard Deviation(up_long_hemisp_std)
• Upwelling longwave hemispheric irradiance, pyrgeometer, maxima(up_long_hemisp_max)
• Instantaneous upwelling pyrgeometer case thermistor temperature, pyrgeometer(inst_up_long_case_temp)
• Downwelling shortwave hemispheric irradiance, pyranometer, maxima(down_short_hemisp_max)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_short_hemisp_std)