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Entry  Tue Dec 14 19:29:42 2021, Paco, Update, BHD, 1Y0 rack work for LO1 
    Reply  Mon Jan 3 12:05:08 2022, Paco, Update, BHD, 1Y0 rack work for LO2 AS1 AS4 
       Reply  Mon Jan 3 16:46:41 2022, Paco, Update, BHD, 1Y1 rack work for SR2, PR2, PR3 
          Reply  Fri Jan 7 17:54:13 2022, Anchal, Update, BHD, PR2 Sat Amp has a bad channel Screen_Shot_2022-01-07_at_6.05.39_PM.png
             Reply  Fri Jan 7 18:28:13 2022, Koji, Update, BHD, PR2 Sat Amp has a bad channel 
                Reply  Mon Jan 10 13:35:52 2022, Anchal, Update, BHD, PR2 Sat Amp has a bad channel 
                   Reply  Mon Jan 10 15:59:46 2022, Koji, Update, BHD, PR2 Sat Amp has a bad channel 6x
                      Reply  Mon Jan 10 17:04:47 2022, Anchal, Update, BHD, AS1 Sat Amp CH2 had offset 
Message ID: 16565     Entry time: Mon Jan 10 17:04:47 2022     In reply to: 16564
Author: Anchal 
Type: Update 
Category: BHD 
Subject: AS1 Sat Amp CH2 had offset 

We found that there was a small offset (~300 mV) at TP6 and TP8, in PD2 circuit (CH2 of the board). I replaced U3 AD822ARZ but did not see any affect. I disconnected the adaptor board in the back and saw that the offset went away. This might mean that the cable had some flaky short to a power supply pin. However, when I just reinserted the adaptor board back again, there was no offset. We could not find any issue with the board after that to fix, so we left it as it is. If this board gives offset issues in the future, most probably the ribbon cable would be the suspect.

Now all ADC channels are showing no offset or overflows in C1SU2 chassis.

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