TGBT14A_912_141 Check Modes 4-6 BOF file again

Goals

  • Test version 136 of L1/LBW1 BOF

Details

  • Start setting up at 8:00am
  • Start with X-band
  • Run 8bank_simple_Xband_mode4
  • 8:17am - Scan 1 - didn't seem to get filled. Try again
  • Scan 2 - still have version 134!
  • Turn VEGAS off, and Bank G crashes. Turn on again, and re-configure. Doesn't fix it. Per Ray, switch to a different mode, then switch back to 4.
  • But, Ray has still not put the correct version of the BOF in.
  • VEGAS crashes, and hangs up astrid. Ray futzes around again
  • scan 5 Mode 4 with version 136 BOF
  • Cal on and Cal off look ~ identical. But this time, the filtersnap ADC counts look wrong. Nogain is pegged at +/- 127, gain has a sharp spike at 0.
  • Bank A J1 converter rack attenuator has a gain of 14.75. Increase by 9dB to 23.75. VEGASDM changes to -29dB, as expected.
  • Add another 6, so dBFS is now -35dB. Still no effect.
  • Switch to optical receiver 2, so J1 is getting no power. Input snapblock= -46dB (basically, all counts are zero). filtersnap_nogain is still +/- 127.

  • Switch back to release version (Sep 8th build of version 134.)
  • Scan 6 - all looks normal. But on close inspection, filtersnap (with gain) looks smaller and narrower, even though dBFS values are the same. This is presumably because of the factor of eight decimation in the (repeat) individual ADC values.

  • Switch to 133 - Randy thinks this is a "good" design (it has a smaller left shift somewhere)
  • Scan 7 Shows the same behavior as 136.

  • Switch to 134 Sep 08 (release version) mode 4
  • Scan 8 - check everything is good.
  • Scan 9 - mode 7. BOF is V133 July 29. Spectra looks good. lbw_gain Bank A 4304064
  • finito

-- RichardPrestage - 2015-12-10

This topic: CICADA > WebHome > GreenBankSpectrometer > CICADAGreenBankSpectrometerCommissioningLogs > CICADAGreenBankSpectrometer2015Dec10
Topic revision: 2015-12-10, RichardPrestage
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