NSA/SHEBA - SKYRAD IRT

A SKYRAD lens (S921) was put on a spare IRT that was configured and 
calibrated with a GNDRAD lens (M6) and the spare (with the wrong lens)
was used to replace the SKYRAD IRT. Here is Kevin Widener's explanation:

"Several weeks ago we experienced an intermittant failure of the SKYRAD IRT.  It 
was outputing voltages greater than 10 vdc which was upsetting the Coastal data 
logger and adjacent channels.  Since we had one spare (an IRT with GNDRAD lens),
we swapped the lenses on 3/28/98 and sent the bad IRT back to the mainland.  We 
have come to learn that the IRTs are calibrated with their lenses and we can't 
just swap the lens."

The SKYRAD IRT was replaced on 4/23/98 with a spare that was properly calibrated 
with a SKYRAD lens. At this time the IRT and datalogger were configured to 
decrease the minumum measurable temperature from -50 to -60 C and to increase
the temperature resolution four times.

• PIR shaded minimum(pirs_min)
• PIR1 mean(pir1_mean)
• Raw data filename(filename)
• lon(lon)
• NIP maximum(nip_max)
• IRT1 maximum(irt1_max)
• PSP shaded maximum(psps_max)
• External voltage(external_voltage)
• PIR1 unshaded maximum(pir1_max)
• PIR shaded standard deviation(pirs_sd)
• PSP shaded mean(psps_mean)
• NIP minimum(nip_min)
• NIP standard deviation(nip_sd)
• UVB minimum(uvb_min)
• PSP1 unshaded minimum(psp1_min)
• North Latitude(lat)
• Time offset from base_time(time_offset)
• PSP1 unshaded standard deviation(psp1_sd)
• Data Logger Temperature(logger_temp)
• UVB mean(uvb_mean)
• PIR1 minimum(pir1_min)
• NIP mean(nip_mean)
• -180.0 - +180.0(alt)
• UVB maximum(uvb_max)
• IRT1 standard deviation(irt1_sd)
• PIR shaded mean(pirs_mean)
• PSP1 maximum(psp1_max)
• Bit data. See details.(bit_data)
• PSP shaded standard deviation(psps_sd)
• PIR shaded maximum(pirs_max)
• IRT1 minimum(irt1_min)
• Internal voltage(internal_voltage)
• PSP1 mean(psp1_mean)
• PIR1 unshaded standard deviation(pir1_sd)
• PSP shaded minimum(psps_min)
• IRT1 mean(irt1_mean)
• UVB standard deviation(uvb_sd)
• base time in epoch(base_time)