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Message ID: 1081     Entry time: Thu Sep 23 22:07:55 2010
Author: Zach & Alastair 
Type: Laser 
Category: GYRO 
Subject: CCW OLTF 

Attached are the new gyro CCW OLTFs with and without the twin-T notch to cut out the 24kHz resonance. The UGF is ~8.5 kHz without the notch and ~12kHz with it. The notch filter needs to be better optimized for the application, as it's not really buying us that much bandwidth at the moment.

In any case, the low-frequency gain is much better now that we have the 1/f2 region back in place (see earlier entries). We can now tap the table reasonably hard with a ball driver, drop bolts/BNC adapters onto it, or clang stools around without dropping lock.

The CCW error signal is being acquired and we will post a spectrum shortly.

CCW_OLTF_9_23_10.pngCCW_OLTF_notch_9_23_10.png

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