40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Entry  Wed Oct 24 14:15:34 2012, Ayaka, Update, Adaptive Filtering, microphone noise mic_open.pngmic_noise.png
    Reply  Wed Oct 24 15:29:52 2012, rana, Update, Adaptive Filtering, microphone noise 
       Reply  Wed Oct 24 17:02:01 2012, Jenne, Update, Adaptive Filtering, microphone noise 
       Reply  Wed Oct 24 22:20:24 2012, Den, Update, Adaptive Filtering, microphone noise mic_64k.pdf
          Reply  Thu Oct 25 09:53:23 2012, Ayaka, Update, Adaptive Filtering, microphone noise 
          Reply  Thu Oct 25 10:03:38 2012, rana, Update, Adaptive Filtering, microphone noise 
             Reply  Thu Oct 25 14:39:14 2012, Den, Update, Adaptive Filtering, microphone noise 
Message ID: 7623     Entry time: Thu Oct 25 14:39:14 2012     In reply to: 7622
Author: Den 
Type: Update 
Category: Adaptive Filtering 
Subject: microphone noise 

Quote:

  That's no good - we need BLRMS channels for many PEM channels, not just two. And the channel names should have the same name as they had in the past so that we can look at long term BLRMS trends.

I suggest:

  1. Have a separate model for Mics and Magnetometers. This model should run at 32 kHz and not have low frequency poles and zeros. Still would have acoustic frequency BLRMS.
  2. Have a low frequency (f_sample = 2 kHz) model for seis an acc. Seismometers run out of poop by 100 Hz, but we want to have the ACC signal up to 800 Hz since we do have optical mount resonances up to there.
  3. Never remove or rename the BLRMS channels - this makes it too hard to keep long term trends.
  4. Do a simple noise analysis to make sure we are matching the noise of the preamps to the noise / range of the ADCs.
  5. Immediately stop using bench supplies for the power. Use ONLY fused, power lines from the 1U rack supplies.

Ayaka, Den

 C1PEM model is back to 2K.

We created a new C1MIC model for microphones that will run at 32K. C1SUS machine is full, we have to think about rearrangement.

For now, we created DQ channels for microphones inside iop model, so we can subtract noise offline.

We provided 0-25 kHz bandwidth noise to AA board and saw the same signal in the output of ADC in the corresponding channel. So cut-off frequency is higher then 25 kHz. There is a label on the AA board that all filters are removed. What does this mean?

We've turned off AA bench power supply, prepare to use fused from 1U.

ELOG V3.1.3-