SGP/SIRS/E25 - Missing 20s and 40s Instantaneous Data

This datastream is missing the 20 and 40 second data outputs, the 60 second output is 
correct.  No other datastreams from SGP SIRS E25 for this time period are affected by the 
missing data.

Only 60s instantaneous data are available; use data with caution

• North Latitude(lat)
• Time offset from base_time(time_offset)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Shaded
  Pyrgeometer(inst_down_long_shaded_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 Case Thermistor Resistance, Pyrgeometer(inst_up_long_case_resist)
• Instantaneous Upwelling Pyrgeometer Thermopile Pyrgeometer(inst_up_long_hemisp_tp)
• Instantaneous Upwelling Shortwave Hemispheric Irradiance, Pyranometer(inst_up_short_hemisp)
• Instantaneous Upwelling Pyrgeometer Dome Thermistor Resistance Pyrgeometer(inst_up_long_dome_resist)
• base time in epoch(base_time)
• Instantaneous uncorrected downwelling shortwave diffuse, shaded pyranometer
  thermopile voltage(inst_diffuse)
• lon(lon)
• Instantaneous direct normal shortwave irradiance, pyrheliometer thermopile
  voltage(inst_direct_normal)
• -180.0 - +180.0(alt)