TGBT15A_915_72 - testing RAMPS / KEYSTONE configurations


  • Try and understand the IF configuration for these projects


  • Start at 9:15am.
  • Copy scripts onoff_L11_original and onoff_L11_test to our project directory
  • All sorts of problems with our understanding, trying to run their scripts.
  • Discovered that Astrid is apparently not re-reading the python script - put the config into the Astrid script.

What we know / have discovered

  • Mapping of beams to VEGAS banks is as follows:
    • B2 -> A, B4 -> B, B5 -> C, B6 -> D, B1 -> E, B1 -> F, B3 -> G, B7 - H
    • So, beam 1 goes to E and F. Not sure which one is not multiplexed, since IF Manager shows they both have a diplexer?
  • The dopplertrack frequency somehow affects the IF - but how?
  • Choose two windows, slightly less than 1.25 GHz apart, explicitly choose both in Bank E, all works as expected.
  • Remove explicit Bank E. Still sub-bands, as expected.
  • Move the windows to be 1.5 GHz apart. Switches to two banks, as expected.
  • Move to Bank2 - still works
  • Move two windows to be 2.5 GHz apart - doppler track 23250, freqs 22000, 24525. Does not configure correctly.
  • Put doppler track same as one, so doppler track 24525, freqs 22000, 24525. Does not configure correctly. Why not?
  • As above. Set broadband = 1. This now works, using Banks A and B.
  • cannot set beam = -1 with broadband = 1. Set beam = -1, broadband = 0, reverts to E and F, and gets it wrong.
  • Cannot set broadband=1 for more than 1 beam
  • Set one frequency to all seven beams, and then the second to beam 1 only. Does not configure correctly for 2.5 GHz apart. beam 1 or -1 makes no difference.
  • Does configure correctly when lines are 1.5 GHz apart. Beam of -1 and 1 makes no difference.

-- RichardPrestage - 2016-11-15
Topic revision: r2 - 2016-11-15, RichardPrestage
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