SGP/MWR/B4 - Serial communications problems

Serial communications errors between MWR and computer due to "lock up" of fiber optic 
driver causing missing and suspect data.

On 2/5/96 instrument mentor received a call from the Vici operator that the MWR was 
reporting COM TIMEOUT messages.  She said she noticed this when she arrived at the site on 
Monday morning, so the problem could have begun Friday evening after she left.

I directed her to check the serial data cable connections.  She reported that all seemed 
tight and informed Site Operations that a service call was necessary.
 
On 2/6/96 Tim Groves contacted me from Vici and reported that a fiber optic driver was 
"locked up" and that he had reset the device and re- established communications with the MWR.
 
Tim also reported that the MWR was not indicating proper internal temperatures and would 
not exit its initialization/warmup phase as a result.  (One of the blackbody temperatures 
was 0 Kelvins.)  I directed him in testing the voltages of these RTDs read by the MWR A/D 
using his computer.  They checked out OK.  I then directed Tim to reboot the MWR 
computer.  This resolved the problem - the temperatures were properly indicated and the MWR 
proceeded to begin data acquisition.

Use data with caution

• (Raw data stream - documentation not supported)

• Actual elevation angle(actel)
• Mean 23.8 GHz sky brightness temperature(tbsky23)
• Sky Infra-Red Temperature(sky_ir_temp)
• Actual Azimuth(actaz)
• 31.4 GHz sky brightness temperature(31tbsky)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• 23.8 GHz sky brightness temperature(23tbsky)
• IR Brightness Temperature(ir_temp)
• Total water vapor along LOS path(vap)
• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• Averaged total liquid water along LOS path(liq)

• (Raw data stream - documentation not supported)

• Total water vapor along LOS path(vap)
• Sky Infra-Red Temperature(sky_ir_temp)
• Mean 23.8 GHz sky brightness temperature(tbsky23)
• Averaged total liquid water along LOS path(liq)
• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• Mean 31.4 GHz sky brightness temperature(tbsky31)

• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• 23.8 GHz noise injection brightness temperature(23unoise)
• 23.8 GHz Blackbody signal(23bb)
• 31.4 GHz sky signal(31sky)
• Averaged total liquid water along LOS path(liq)
• 31.4 GHz noise injection brightness temperature(31unoise)
• 31.4 GHz sky brightness temperature(31tbsky)
• Which LOS configuration(losn)
• Mixer kinetic (physical) temperature(tkxc)
• 31.4 GHz blackbody+noise injection signal(31bbn)
• Blackbody kinetic temperature(tkbb)
• 31.4 GHz blackbody(31bb)
• IR Brightness Temperature(ir_temp)
• 23.8 GHz sky brightness temperature(23tbsky)
• Actual elevation angle(actel)
• 31.4 GHz sky+noise injection signal(31skyn)
• 23.8 GHz blackbody+noise injection signal(23bbn)
• 23.8 GHz sky+noise injection signal(23skyn)
• Actual Azimuth(actaz)
• Total water vapor along LOS path(vap)
• 23.8 GHz sky signal(23sky)