MIF (General)takaaki.yokozawa - 13:25 Thursday 21 November 2024 (31716)
Print this reportDAC noise evaluation for ETMXI performed the noise budget of the DAC noise for ETMX by turned off(on) the de-whitening filters in coil driver. ITMX TM 1 stage -> 0 stage (off) ITMX IMH/IMV 0 stage -> 1 stage (on) ITMX MNH/MNV 2 stage -> 0 stage (off)
Similar results with other Type-A suspensions, we can see the excess when we turned off the de-whitening filter for the TM and MNV as shown in Fig.1. and Fig.2. MNH no significant excess as shown in Fig.3.
I noticed the IMH and IMV were not performed the de-whitening filter, so I checked the spectrum when I turned on the de-whtening filter, then the noise level can be reduced(around 40 Hz) when performed it to IMV.
I changed the LSC_LOCK guardian to add the de-whitening filter to IMH and IMV at the same timing when we turned on the de-whitening filter to MNH and MNV. If you noticed some trouble, please remove the L2054 and L2055 from LSC_LOCK guardian. ezca['VIS-ETMX_BIO_IMH_STATEREQ'] = 2 ezca['VIS-ETMX_BIO_IMV_STATEREQ'] = 2
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shinji.miyoki - 13:47 Thursday 21 November 2024 (31717)
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Could you please explain Fig.4? It shows the reduction of displacement.