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Before the track

  • Configure the Block 0 rack
    • Amplify, attennuate, mix etc to IFP1, 2
    • Set the 2nd LOs
  • start DAS software
    • In a pcfs42 terminal type “start_DAS.csh”
    • Set the appropriate configuration (e.g
    • Don't forget to press “S” for setup.
    • adjust attenuators to get the levels in range. Check this again once the receivers are configured.
  • On tidvsi (
    • check time
    • start disko. Type “disko” at the prompt.
      • set the disk to write to, the experiment name and recorder configuration
      • Set it to start recording at a specified time and the duration.
  • PCFS. The PCFS will have the wrong time if it has been a while since it was last used. It gets its time from the S2. To set the time:
    • plug the S2 into the DAS, connecting the DAS S2 Out to the the S2 C1 port
    • from a terminal, type “telnet s2” and set the time using the “time” then the “time validate” commands.
    • start the PCFS software. On the pcfs42:1 VNC display:
      • ssh ops@pcfs42
      • pcfsa-remote
      • Choose S2, the bands you want, and maintenance mode
      • The pcfs software will start and the time will be synchronised with the S2
      • exit the pcfs software by typing “terminate” in the oprin window
  • Configure the cabling from the DAS to the VSIC.
  • Re-start the PCFS software as before, then start the schedule, e.g. in the oprin window:
    • schedule=v190dti
    • ifds
    • vclba
    • configure PCFS attenuators etc with the ifd command
  • Tsys monitoring. If using S or X-band, use the DCCs to log SNT (Tsys) by modulating a 0.25 or 0.5K diode. For other bands xplot or the squarelaw sampler can be used. Usually xplot is sufficient:
    • on pcfs40: /usr2/st/vlbisrv/start_vlbisrv dflt
    • on eac40: /opt/rmc/bin/xplot -rh pcfs40
    • In the xplot window, choose IF1 or IF2, and start the logging function. Also note if the time on the EAC is different to UT. If it is, note the difference as it can be corrected for later. A good way to check the time and measure an offset is to turn a diode on and note the time. Look for the change in power in the log and see if the time is the same or not.
lbaops/tidnotes/beforethetrack.txt · Last modified: 2015/12/18 16:39 by