TWP/MFRSR/C2 - Heater board failing

This DQR documents a long period of heater board(s) in the process of failing.  At the 
start of this period the telltale signs of a heater board in the beginning stages of failure 
were evident.  But what started as a straightforward situation morphed into an extended 
problem compounded by the remoteness of the site and faulty replacement boards.  This 
sent us down multiple wrong paths trying to diagnose the problem.

The problem occurred in two phases, heater board failing and heater board failed.  The 
first phase is documented here and the second phase is documented in D130530.3.  

During the period specified, the heater board(s) had not completely failed, so the bulk of 
the data are probably OK.

• optical depth for the Direct BroadBand(barnard_optical_depth_broadband)
• optical depth for the Direct BroadBand(michalsky_optical_depth_broadband)
• Angstrom exponent(michalsky_angstrom_exponent)
• optical depth for the Direct Narrowband Filter2(barnard_optical_depth_filter2)
• optical depth for the Direct Narrowband Filter3(barnard_optical_depth_filter3)
• optical depth for the Direct Narrowband Filter1(barnard_optical_depth_filter1)
• optical depth for the Direct Narrowband Filter6(barnard_optical_depth_filter6)
• optical depth for the Direct Narrowband Filter4(barnard_optical_depth_filter4)
• optical depth for the Direct Narrowband Filter5(barnard_optical_depth_filter5)
• optical depth for the Direct Narrowband Filter1(michalsky_optical_depth_filter1)
• optical depth for the Direct Narrowband Filter2(michalsky_optical_depth_filter2)
• optical depth for the Direct Narrowband Filter3(michalsky_optical_depth_filter3)
• optical depth for the Direct Narrowband Filter4(michalsky_optical_depth_filter4)
• optical depth for the Direct Narrowband Filter5(michalsky_optical_depth_filter5)
• optical depth for the Direct Narrowband Filter6(michalsky_optical_depth_filter6)
• Angstrom exponent(barnard_angstrom_exponent)

• log(irradiance) for the Direct Narrowband Filter3, Michalsky(michalsky_lnI_filter3)
• log(irradiance) for the Direct Narrowband Filter4, Michalsky(michalsky_lnI_filter4)
• log(irradiance) for the Direct Narrowband Filter5, Michalsky(michalsky_lnI_filter5)
• log(irradiance) for the Direct Narrowband Filter6, Michalsky(michalsky_lnI_filter6)
• log(irradiance) for the Direct Narrowband Filter1(michalsky_lnI_filter1)
• log(irradiance) for the Direct Narrowband Filter2, Michalsky(michalsky_lnI_filter2)
• log(irradiance) for the Direct Broadband(michalsky_lnI_broadband)
• log(irradiance) for the Direct Broadband(barnard_lnI_broadband)
• log(irradiance) for the Direct Narrowband Filter5(barnard_lnI_filter5)
• log(irradiance) for the Direct Narrowband Filter4(barnard_lnI_filter4)
• log(irradiance) for the Direct Narrowband Filter6(barnard_lnI_filter6)
• log(irradiance) for the Direct Narrowband Filter1, Barnard(barnard_lnI_filter1)
• log(irradiance) for the Direct Narrowband Filter3, Barnard(barnard_lnI_filter3)
• log(irradiance) for the Direct Narrowband Filter2, Barnard(barnard_lnI_filter2)

• Narrowband Direct Horizontal Irradiance, Filter 5, cosine corrected(direct_horizontal_narrowband_filter5)
• Narrowband Direct Horizontal Irradiance, Filter 6, cosine corrected(direct_horizontal_narrowband_filter6)
• Direct horizontal narrowband irradiance, filter 1(direct_horizontal_narrowband_filter1)
• Diffuse narrowband hemispheric irradiance, filter 1(diffuse_hemisp_narrowband_filter1_raw)
• Narrowband Direct Horizontal Irradiance, Filter 2, cosine corrected(direct_horizontal_narrowband_filter2)
• Direct Horizontal Narrowband Irradiance, Filter 3(direct_horizontal_narrowband_filter3)
• Narrowband Direct Horizontal Irradiance, Filter 4, cosine corrected(direct_horizontal_narrowband_filter4)
• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2)
• Narrowband Hemispheric Irradiance, Filter 1, offset corrected(hemisp_narrowband_filter1)
• Narrowband hemispheric irradiance, filter 4, offset and cosine corrected(hemisp_narrowband_filter4)
• Narrowband hemispheric irradiance, filter 3, offset and cosine corrected(hemisp_narrowband_filter3)
• Narrowband hemispheric irradiance, filter 6, nominal wavelength is 935 nm(hemisp_narrowband_filter6)
• Narrowband Hemispheric Irradiance, Filter 5, offset corrected(hemisp_narrowband_filter5)
• Alltime narrowband hemispheric irradiance, filter 5(alltime_hemisp_narrowband_filter5)
• Alltime Narrowband Hemispheric Irradiance, Filter 4(alltime_hemisp_narrowband_filter4)
• Alltime Narrowband Hemispheric Irradiance, Filter 6(alltime_hemisp_narrowband_filter6)
• Alltime narrowband hemispheric irradiance, filter 1(alltime_hemisp_narrowband_filter1)
• Alltime Narrowband Hemispheric Irradiance, Filter 3(alltime_hemisp_narrowband_filter3)
• Alltime narrowband hemispheric irradiance, filter 2(alltime_hemisp_narrowband_filter2)
• Hemispheric broadband irradiance(hemisp_broadband_raw)
• Diffuse narrowband hemispheric irradiance, filter 6(diffuse_hemisp_narrowband_filter6_raw)
• Narrowband hemispheric irradiance, filter 2(hemisp_narrowband_filter2_raw)
• Diffuse Narrowband Hemispheric Irradiance, Filter 6, offset corrected(diffuse_hemisp_narrowband_filter6)
• Alltime hemispheric broadband irradiance(alltime_hemisp_broadband)
• Narrowband diffuse hemispheric irradiance, filter 5, offset and cosine corrected(diffuse_hemisp_narrowband_filter5)
• Diffuse Narrowband Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4)
• Narrowband hemispheric irradiance, filter 4(hemisp_narrowband_filter4_raw)
• Diffuse narrowband hemispheric irradiance, filter 4(diffuse_hemisp_narrowband_filter4_raw)
• Narrowband Hemispheric Irradiance, Filter 6(hemisp_narrowband_filter6_raw)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2(diffuse_hemisp_narrowband_filter2_raw)
• Diffuse Hemispheric Broadband Irradiance(diffuse_hemisp_broadband_raw)
• Diffuse Narrowband Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2, offset corrected(diffuse_hemisp_narrowband_filter2)
• Diffuse Narrowband Hemispheric Irradiance, Filter 1, offset corrected(diffuse_hemisp_narrowband_filter1)
• Narrowband hemispheric irradiance, filter 1(hemisp_narrowband_filter1_raw)
• Direct Horizontal Broadband Irradiance(direct_horizontal_broadband)
• Narrowband Hemispheric Irradiance, Filter 3(hemisp_narrowband_filter3_raw)
• Hemispheric broadband irradiance(hemisp_broadband)
• Diffuse narrowband hemispheric irradiance, filter 3(diffuse_hemisp_narrowband_filter3_raw)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• Narrowband hemispheric irradiance, filter 5(hemisp_narrowband_filter5_raw)
• Diffuse Narrowband Hemispheric Irradiance, Filter 5(diffuse_hemisp_narrowband_filter5_raw)

• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2)
• Narrowband Hemispheric Irradiance, Filter 1, offset corrected(hemisp_narrowband_filter1)
• Narrowband hemispheric irradiance, filter 6, nominal wavelength is 935 nm(hemisp_narrowband_filter6)
• Alltime hemispheric broadband irradiance(alltime_hemisp_broadband)
• Narrowband Hemispheric Irradiance, Filter 5, offset corrected(hemisp_narrowband_filter5)
• Narrowband hemispheric irradiance, filter 4, offset and cosine corrected(hemisp_narrowband_filter4)
• Narrowband hemispheric irradiance, filter 3, offset and cosine corrected(hemisp_narrowband_filter3)
• Alltime narrowband hemispheric irradiance, filter 5(alltime_hemisp_narrowband_filter5)
• Alltime Narrowband Hemispheric Irradiance, Filter 4(alltime_hemisp_narrowband_filter4)
• Alltime Narrowband Hemispheric Irradiance, Filter 6(alltime_hemisp_narrowband_filter6)
• Alltime narrowband hemispheric irradiance, filter 1(alltime_hemisp_narrowband_filter1)
• Alltime Narrowband Hemispheric Irradiance, Filter 3(alltime_hemisp_narrowband_filter3)
• Alltime narrowband hemispheric irradiance, filter 2(alltime_hemisp_narrowband_filter2)
• Ratio of direct_normal_broadband to diffuse_hemisp_broadband(direct_diffuse_ratio_broadband)
• Hemispheric broadband irradiance(hemisp_broadband)
• Ratio of direct_normal_narrowband_filter6 to diffuse_hemisp_narrowband_filter6(direct_diffuse_ratio_filter6)
• Diffuse Narrowband Hemispheric Irradiance, Filter 6, offset corrected(diffuse_hemisp_narrowband_filter6)
• Narrowband diffuse hemispheric irradiance, filter 5, offset and cosine corrected(diffuse_hemisp_narrowband_filter5)
• Diffuse Narrowband Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4)
• Ratio of direct_normal_filter1 to diffuse_hemisp_filter1(direct_diffuse_ratio_filter1)
• Ratio of direct_normal_filter2 to diffuse_hemisp_filter2(direct_diffuse_ratio_filter2)
• Ratio of direct_normal_narrowband_filter3 to diffuse_hemisp_narrowband_filter3(direct_diffuse_ratio_filter3)
• Ratio of direct_normal_filter4 to diffuse_hemisp_filter4(direct_diffuse_ratio_filter4)
• Ratio of direct_normal_filter5 to diffuse_hemisp_filter5(direct_diffuse_ratio_filter5)
• Diffuse Narrowband Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2, offset corrected(diffuse_hemisp_narrowband_filter2)
• Diffuse Narrowband Hemispheric Irradiance, Filter 1, offset corrected(diffuse_hemisp_narrowband_filter1)
• Direct horizontal narrowband irradiance, filter 1(direct_horizontal_narrowband_filter1)
• Narrowband Direct Horizontal Irradiance, Filter 2, cosine corrected(direct_horizontal_narrowband_filter2)
• Direct Horizontal Narrowband Irradiance, Filter 3(direct_horizontal_narrowband_filter3)
• Narrowband Direct Horizontal Irradiance, Filter 4, cosine corrected(direct_horizontal_narrowband_filter4)
• Narrowband Direct Horizontal Irradiance, Filter 5, cosine corrected(direct_horizontal_narrowband_filter5)
• Narrowband Direct Horizontal Irradiance, Filter 6, cosine corrected(direct_horizontal_narrowband_filter6)
• Direct normal narrowband irradiance, filter 2, offset corrected(direct_normal_narrowband_filter2)
• Narrowband Direct Normal Irradiance, Filter 3, cosine corrected(direct_normal_narrowband_filter3)
• Narrowband Direct Normal Irradiance, Filter 1(direct_normal_narrowband_filter1)
• Direct normal narrowband irradiance, filter 6, offset corrected(direct_normal_narrowband_filter6)
• Direct normal narrowband irradiance, filter 4, offset corrected(direct_normal_narrowband_filter4)
• Narrowband Direct Normal Irradiance, Filter 5(direct_normal_narrowband_filter5)
• Direct Normal Broadband Irradiance, cosine corrected, broadband scale applied(direct_normal_broadband)
• Direct Horizontal Broadband Irradiance(direct_horizontal_broadband)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)