TGBT14A_912_85 - VEGAS tests with the DCR

Goals

  • Configure VEGAS for cal switching; look at VEGAS IF module monitor with DCR
  • try Modes 1 and 4 with different input levels with X and L band (if time allows)
  • need to check what order Galen has hooked up the test inputs into.

Details

  • Set up at 10am. Need ray to switch versions, etc
  • Note, weather is lousy; thick fog, clouds, rain....
  • X-band in focus, telescope at access, people working in the receiver cabin.

NOTE: some of the higher power levels are significantly overdriving the DCR.

Setup

  • Set up as for session 84, but correct the automated setup of the external input to the Analog Filter Rack

X-band, Mode 4, high cal

  • Scan 1 fails; Antenna is still in scan coordinator
  • bank_gain_mode4_vegas_dcr, converter rack balancing running from targets of -15dB to -27dB (may not always hit target). Three tracks per atten setting
  • Scans 2 - 16

X-band, Mode 4, low cal

  • get just 3 samples on low noise cal for Dave, -15,-18,-21dB
  • scans 17 - 19

X-band, Mode 1, high cal

  • edit bank_gain_mode1_vegas_dcr - Mode 1, high cal, target levels -15dB to -27dB, three tracks on each.
  • scans 20 - 34

L-band, Mode 1, high cal

  • Mode 1, high cal, target levels -15dB to -27dB, three tracks on each.
  • scans 35 - 49

L-band, Mode 4, high cal

  • Mode 4, high cal, target levels -15dB to -27dB, three tracks on each.
  • scans 50 - 64

Noise source into input of ADCs - Mode 1 / 4

  • Goal is to see whether effects move as we change which cables are connected to which VEGAS input.
  • DCR is not relevant here.
  • bank_gain_mode1_cband_nocal
  • archivist
  • Randy hooks up noise source (cables are not labelled). 0dB attenuation corresponds to ~ -15dBFS
  • Scans 65 - 69 = attenuator 0 - 12 dB

  • bank_gain_mode4_cband_nocal
  • setValues with 5.664 * 2**24 /(2 * sqrt2)
  • Scans 70 - VEGAS dies with invalid data error
  • Scans 71 - 75, 0 - 12dB

Noise source into input of ADCs - Mode 1 / 4 - Noise source inputs swapped

  • recable E1 -> G1, E2 -> G2, F1 -> H1, F2 -> H2
  • Still in mode 4
  • Scans 76 - 80, 0 - 12 dB
  • 2:30pm - finito!

-- RichardPrestage - 2015-03-18
Topic revision: r2 - 2015-03-20, RichardPrestage
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