====== Katherine Maintenance Trip (April 12-17) ======

  * DBBC Service - Replaced PCI7200 card, swapped CoMos B & C, reseated stack, connected longer VSI cable to mk5-2ke. No further problems with errorenous readback of power levels, but seem to be suffering a new poblem with clock breaks in the mark5 units. Will revisit earthing of the mark5 units to attempt to correct this problem. 
  * mk5-2ke - Upgraded firmware and software to v3.0.2. Connected to VSI output of DBBC. All working, but still needs an additional counter to fully support its use in recording.
  * Monica - Rxmon & IFBox code updated to read the temperature & Humidity sensors in control room, maser room, pedestal and hub and the maser battery voltage. Feed temp & RH sensor was damaged in installation but monitor points have been created for when it is available. 
  * UPSMon - A new PC has been installed which monitors the UPS state via NUT, and can send SMSs via an attached mobile phone. This should give warning of any significant power outages.
  * Phase CAL - The rapid phase wrapping noted by Brian Corey (Dec 2013) appears to be caused by the 5 MHz filter put in place last year. Removing it reduced the phase rate from 360 degree drifts in ~30 min at S-band (~5 min at X-band), to ~30 degrees over 3 hours at S-band (~120-150 degrees over 3.5 hours at X-band). No delay-like differential variations noted in the pcal phases after removing the filter. 
  * Tsys - SLCP LNA appears to be worse than nominal. Adjusted flange connections of S-band feed while monitoring Tsys under load and have got an apparent improvement in SRCP Tsys (~100-110 K instead of ~130 K). New CAL factors have been measured for the cont CAL per band.
  * pcfske - Discovered that disk 2 of the RAID had failed and that the spare was not in use. Removed disk 2 from the RAID array and set the RAID rebuilding with sda & sdc. 
  * webcamke - Removed webcamke from housing, left housing on pole to avoid a fight with the wasps. A new housing and camera installed further down the pole, replacing webcamke.

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