AIDA GELINA BRIKEN nToF CRIB ISOLDE CIRCE nTOFCapture DESPEC DTAS EDI_PSA 179Ta CARME StellarModelling DCF K40
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Message ID: 414     Entry time: Fri Apr 8 08:59:42 2022
Author: OH, NH 
Subject: Friday 8th April 
09:59 Noticed that the right hand ribbon cable for aida07 was offset vertically by 1. i.e. Only 1 of the 2 rows of pins in. Unbiassed detectors and reconnected.
      Rebiassed detectors - leakage current on DSSD2 increased to 9.96uA - Attachment 1

      Power cycling FEEs

      Following restart the FEEs show some improvement in rates - attachment 2
      Rate spectra - attachment 3
      Still issues with aida11 in the rate spectra (Likely a misaligned ERNI connector)



      Pulser on rate spectra - attachment 4
      Pulser off rate spectra - attachment 5
      We can see that with the pulser on there are events in the channels in aida01 and aida11
      With the pulser off these channels disappear.
      ERNI connector is then likely aligned the issue is more likely the DSSD ribbon cable is misaligned.

      Taking bias off to investigate.


10:39 Could not observe anything out of alignement about either the connectors or the adaptor boards
      Note that after pushing on the connector AIDA01 had largely recovered

13:30 Top of snout taken off while mounted in S4. It was observed that one of the ribbon cables for aida11 was off by 1 row.
      This was corrected in situ and the snout was put back together and made light tight again.
      Oddly leakage current still the same - DSSD2 has come down though - attachment 6
      FEEs powercycled for new tests

      Half the channels in aida11 had appeared again
      Took apart once more and found the other header also off by one row which has been corrected

      FEEs powercycled for new test

      All of aida11 now showing - attachment 7
      Statistics at 0xa shown in attachment 8
      All p+n for DSSD1 are good (aida01, 03, 09, 10, 11 and 12)
      p+n for DSSD2 are so so (aida05, 07, 13, 14, 15 and 16)
      All n+n 2, 4, 6 and 8 are poor still


14:50 p+n waveforms - attachment 9
      n+n waveforms - attachment 10

      Current jumper configuration
      LK1 (Bias ground) on FEEs 6 and 8
      LK2&4 on all p+n
      LK3 on aida03 and aida07 (Bottom middle)

15:00 Investigated whether there was a light leak. Placed black material over snout.
      Leakage on DSSD2 dropped to 5.6 - attachment 11
      There was a light leak
      Stats have decreased slightly - attachment 12

16:00 Move raspberry pis atop 5mm alminimum plate to keep away from FEE64 PSUs
      No change

16:30 Remove pulser network from all FEEs 
      Rates get noticably worse in many FEEs... why?
      Stats - attachment 13

      Possible ideas include braid touching things it shouldn't (Adapter PCBs?) 
Attachment 1: 220408_1000_bias.png  38 kB  Uploaded Fri Apr 8 10:02:13 2022  | Hide | Hide all
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Attachment 2: 220409_1010_Stats.png  81 kB  Uploaded Fri Apr 8 10:11:31 2022  | Hide | Hide all
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Attachment 3: 220409_1011_rate.png  195 kB  Uploaded Fri Apr 8 10:13:11 2022  | Hide | Hide all
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Attachment 4: 220408_1358_bias.png  35 kB  Uploaded Fri Apr 8 13:59:23 2022  | Hide | Hide all
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Attachment 5: 220408_1444_rate.png  202 kB  Uploaded Fri Apr 8 14:47:33 2022  | Hide | Hide all
220408_1444_rate.png
Attachment 6: 220408_1444_stats.png  80 kB  Uploaded Fri Apr 8 14:47:33 2022  | Hide | Hide all
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Attachment 7: 220408_1449_layout7.png  220 kB  Uploaded Fri Apr 8 14:52:24 2022  | Hide | Hide all
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Attachment 8: 220408_1451_layout8.png  163 kB  Uploaded Fri Apr 8 14:52:24 2022  | Hide | Hide all
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Attachment 9: 220308_1459_bias.png  38 kB  Uploaded Fri Apr 8 16:31:10 2022  | Hide | Hide all
220308_1459_bias.png
Attachment 10: 220408_1503_stats_post_light.png  81 kB  Uploaded Fri Apr 8 16:31:14 2022  | Hide | Hide all
220408_1503_stats_post_light.png
Attachment 11: 2022-04-08_16-26-30_Stats_No_Pulser.png  84 kB  Uploaded Fri Apr 8 16:31:17 2022  | Hide | Hide all
2022-04-08_16-26-30_Stats_No_Pulser.png
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