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Entry  Thu Aug 20 00:21:51 2020, gautam, Update, Electronics, First look at HV coil driver IMG_8724.JPGtimeDomain.pdfHVampNoise.pdf
    Reply  Sun Aug 23 23:36:58 2020, gautam, Update, Electronics, First look at HV coil driver IMG_5379.JPGstabilityCriterion.pdf
       Reply  Wed Aug 26 16:12:25 2020, gautam, Update, Electronics, Test mass coil current requirements coilCurrents.png
       Reply  Tue Sep 1 15:39:04 2020, gautam, Update, Electronics, HV coil driver oscillations fixed testSetup.pdfHVampNoise_driven.pdf
          Reply  Thu Oct 22 11:14:47 2020, gautam, Update, Electronics, HV coil driver packaged into 2U chassis HVampNoise_driven_chassis.pdfHVampNoise_dispUnits.pdfD1900163_measurementSetup.zip
             Reply  Thu Oct 22 13:04:42 2020, rana, Update, Electronics, HV coil driver packaged into 2U chassis 
                Reply  Thu Oct 22 22:01:53 2020, gautam, Update, Electronics, HV coil driver packaged into 2U chassis DACnoiseFilterGain.pdfDACnoiseFilterNoises.pdf
                   Reply  Fri Oct 23 09:03:43 2020, anchal, Update, Electronics, HV coil driver packaged into 2U chassis 
             Reply  Thu Nov 12 14:55:35 2020, gautam, Update, Electronics, More systematic noise characterization powerSupplyNoise.pdfcoherence.pdf
                Reply  Thu Nov 12 15:40:42 2020, Koji, Update, Electronics, More systematic noise characterization 
                   Reply  Mon Nov 16 00:02:34 2020, rana, Update, Electronics, More systematic noise characterization 
                      Reply  Wed Jan 20 10:13:06 2021, gautam, Update, Electronics, HV Power supply bypassing bypassCaps.pdfIMG_9079.jpgIMG_9078.jpgHVampNoise_driven_chassis.pdfprintCoilCurrents.pdf
                         Reply  Mon Feb 1 12:30:21 2021, gautam, Update, Electronics, More careful characterization HVPS.pdfHV_testckt.pdftotalNoise.pdf
                         Reply  Wed Feb 10 21:14:03 2021, gautam, Update, Electronics, Production version of the HV coil driver tested inputDiffRecTF.pdfLVnoises.pdftotalNoise.pdftimeDomainTests.pdf
                            Reply  Fri Feb 26 16:31:02 2021, gautam, Update, Electronics, Production version of the HV coil driver tested with KEPCO HV supplies totalNoise_KEPCO.pdf
                               Reply  Fri Feb 26 20:20:43 2021, Koji, Update, Electronics, Production version of the HV coil driver tested with KEPCO HV supplies 
                                  Reply  Sat Feb 27 17:25:42 2021, gautam, Update, Electronics, Production version of the HV coil driver tested with KEPCO HV supplies 
                                     Reply  Thu May 20 16:56:21 2021, Koji, Update, Electronics, Production version of the HV coil driver tested with KEPCO HV supplies P_20210520_154523_copy.jpg
Message ID: 15848     Entry time: Sat Feb 27 17:25:42 2021     In reply to: 15847     Reply to this: 16148
Author: gautam 
Type: Update 
Category: Electronics 
Subject: Production version of the HV coil driver tested with KEPCO HV supplies 

I will try the test of switching out KEPCOs one at a time for the HP. Given that the passive RC filter doesn't filter out the excess, I am wondering if the KEPCO is somehow polluting the circuit ground? The measurement was made between the circuit side of R24 (see schematic) and a ground testpoint, so the passive R23/C15 pole should filter the noise above ~15 Hz.

Quote:

This is very disappointing. Even with KEPCO linear supply with the improved HV driver circuit, the noise level is significantly higher than the 20kOhm R thermal noise.

What is special with the HP supplies? Can you replace KEPCOs with the HP supply, one by one to specify which one is making the noise bad?

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