ALMA Band 6 Cold Amplifier Oscillation in the 3rd Stage


  • Resonance due to circuit size
  • Seen in lab as excess power in a single channel with 1 MHz RB on a spectrum analyzer
  • Typical frequency range is 229-230 GHz, but could be a bit larger
  • Expected to be different on different antennas and different polarizations
  • spectrum analyzer traces from Band 6 group

Possible FDM Datasets to check

Object Date uidSorted ascending auto-corr cross-corr
R Scl (CO 2-1) 2010 Nov 26 uid___A002_X16c110_X1c3

Possible TDM Datasets to check

Object Date uid auto-corr cross-corr script
NGC253-230 GHz 2010 Sep 11 uid___A002_X1288b6_X273 XX   YY XX   YY  
NGC4038-230 GHz 2011Apr04 uid___A002_X1c99f2_X1ce, X30b, X455 and X59e   Band6NGC4038

-- ToddHunter - 2011-04-11
Topic attachments
I Attachment Action Size Date Who Comment
FE020Band6Spurious.pdfpdf FE020Band6Spurious.pdf manage 340 K 2011-04-11 - 12:43 ToddHunter spectrum analyzer traces from Band 6 group
Topic revision: r5 - 2011-04-25, ToddHunter
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