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Entry  Tue Jun 25 19:18:07 2013, gautam, Configuration, endtable upgrade, plan of action for PZT installation 
    Reply  Wed Jul 3 21:19:04 2013, gautam, Configuration, endtable upgrade, plan of action for PZT installation DAC_bank.pngASC_schematic.pdf
       Reply  Mon Jul 8 13:45:19 2013, gautam, Configuration, endtable upgrade, Driver board verification 
          Reply  Wed Jul 10 22:41:06 2013, gautam, Configuration, endtable upgrade, PZT Driver Board HV_Amplifier.pdf
             Reply  Thu Jul 11 23:50:57 2013, gautam, Configuration, , PZT Driver Board-changes made ASC_schematic.pdfDAC_Max_output.JPG
                Reply  Mon Jul 15 11:51:18 2013, gautam, Configuration, endtable upgrade, DAC at 1Y4-Max Output and Power Spectrum max_amp.JPGmax_amp_all_channels.JPGDACOffPowerSpec.pdfDACOnPowerSpec.pdfDAC2kPowerSpectrum.pdf
                   Reply  Mon Jul 15 13:51:17 2013, Koji, Configuration, endtable upgrade, DAC at 1Y4-Max Output and Power Spectrum 
                      Reply  Mon Jul 15 15:54:20 2013, gautam, Configuration, endtable upgrade, DAC at 1Y4- Power Spectrum -with the right units DACOffPSD.pdfDAC500PSD.pdfDAC2000PSD.pdf
                         Reply  Mon Jul 15 17:20:43 2013, Jenne, Configuration, endtable upgrade, DAC at 1Y4- Power Spectrum -with the right units 
                            Reply  Mon Jul 15 17:59:31 2013, gautam, Configuration, endtable upgrade, DAC at 1Y4- Power Spectrum -6.4kHz bandwidth DAC-6.4_kHz_BW_PSD.pdf
                               Reply  Tue Jul 16 14:51:09 2013, gautam, Configuration, endtable upgrade, AI Board-D000186-Modified notches D000186_Frequency_Response.pdf
                                  Reply  Thu Jul 18 19:09:08 2013, gautam, Configuration, endtable upgrade, QPD Calibration for PZT Calibration QPD-XCalib.pdfQPD-YCalib.pdfError_Function_Fitting.zip
                                     Reply  Thu Jul 18 20:20:52 2013, gautam, Configuration, endtable upgrade, First mirror glued to PZT and mounted in modified mounts Piezo-mirror.jpg
                                        Reply  Thu Jul 18 23:34:40 2013, gautam, Configuration, endtable upgrade, Coarse adjustment of PZT axes orientation in mount PZT_out_waveform.jpg
                                           Reply  Fri Jul 19 23:35:31 2013, gautam, Configuration, endtable upgrade, Preliminary Calibration of PZT QPD-XCalib.pdfQPD-YCalib.pdfPiezo_Yaw_Calib-in_QPD_linear_range-Pitch_tilt.pdfPiezo_Yaw_Calib-in_QPD_linear_range-Yaw_tilt.pdf
                                              Reply  Tue Jul 23 20:41:40 2013, gautam, Configuration, endtable upgrade, Full range calibration and installation of PZT-mounted mirrors M1_Pitch_calib.pdfM1_Yaw_calib.pdfM2_Pitch_calib.pdfM2_Yaw_calib.pdfPI_S330.20L.pdf
                                                 Reply  Mon Aug 5 18:48:44 2013, gautam, Configuration, endtable upgrade, Full range calibration of PZT mounted mirrors for Y-endtable 2-inch-CVI-Yawcalib.pdf2-inch-CVI-Pitchcalib.pdf1-inch-Laseroptik-Yawcalib.pdf1-inch-Laseroptik-Pitchcalib.pdf
                                        Reply  Fri Jul 19 22:51:40 2013, gautam, Configuration, endtable upgrade, Second mirror glued to PZT and mounted  Piezo-mirror_2.JPG
                                           Reply  Tue Jul 30 19:44:05 2013, gautam, Configuration, endtable upgrade, Second mirror glued to PZT and mounted  
                                  Reply  Thu Jul 18 21:12:58 2013, gautam, Configuration, endtable upgrade, AI Board-D000186-All channels modified AI_Board_Output.jpg
                Reply  Mon Jul 29 13:39:25 2013, gautam, Configuration, endtable upgrade, PZT Driver Board-further changes D980323-C-modified.pdfD980323-C-modified-pg2.pdf
          Reply  Mon Jul 29 21:57:45 2013, gautam, Configuration, endtable upgrade, Hardware installed at 1X9 
             Reply  Tue Jul 30 19:40:47 2013, gautam, Configuration, endtable upgrade, DAC-PZT Driver Board Output Signal Chain Tested 
Message ID: 8857     Entry time: Tue Jul 16 14:51:09 2013     In reply to: 8853     Reply to this: 8873   8875
Author: gautam 
Type: Configuration 
Category: endtable upgrade 
Subject: AI Board-D000186-Modified notches 

 I tried shifting the notch frequencies on the D000186-revision D board given to me by Koji. The existing notches were at ~16 kHz and ~32 kHz. I shifted these to notches at ~64 kHz and ~128 kHz by effecting the following changes (see schematic for component numbering) on Channel 8 of the board-I decided to check things out on one channel before implementing changes en masse:

  • R6 and R7 replaced with 511 ohm smts
  • R8 replaced with 255 ohm smt
  • R14 and R15 replaced with 549 ohm smts
  • R16 replaced with 274 ohm smt

=> New notches should be at 66.3 kHz and 131.7 kHz.

I then measured the frequency response of the modified channel using the SR785, and compared it to the response I had measured before switching out the resistors. The SR785 only goes up to 102 kHz, so I cannot verify the 128 kHz notch at this point. The position of the 64 kHz notch looks alright though. I think I will go ahead and switch out the remaining resistors in the evening.

Note 1: These plots are just raw data from the SR785, I have not tried to do any sort of fitting to poles and zeros. I will do this at some point. 

Note 2: All these smts were taken from Downs. Todd helped me locate the non-standard value resistors. I also got a plastic 25-pin D-sub backshells (the spares are in the rack), with which I have fashioned the required custom ribbon cables (40 pin IDC to 25 pin D-sub with twisted ribbon wire, and a short, 10pin IDC to 10pin IDC with straight ribbon wire).

D000186_Frequency_Response.pdf

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