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Entry  Tue Mar 16 16:02:33 2021, Koji, Update, LSC, REFL11 demod retrofitting IMG_0545.jpegIMG_0547.jpegD040179-A.pdfIMG_0548.jpegIMG_0550.jpeg
    Reply  Thu Mar 18 07:02:27 2021, Koji, Update, LSC, REFL11 demod retrofitting TFs.pdfPSD.pdf
Message ID: 15936     Entry time: Thu Mar 18 07:02:27 2021     In reply to: 15923
Author: Koji 
Type: Update 
Category: LSC 
Subject: REFL11 demod retrofitting 

Attachment 1: Transfer Functions

The original circuit had a gain of ~20 and the phase delay of ~1deg at 10kHz, while the new CH-I and CH-Q have a phase delay of 3 deg and 2 deg, respectively.

Attachment 2: Output Noise Levels

The AD797 circuit had higher noise at low frequency and better noise levels at high frequency. Each TLE2027 circuit was tuned to eliminate the instability and shows a better noise level compared to the low-frequency spectrum of the AD797 version.

RXA: AD797 sad, all hail the op-amps ending with 27 !

Attachment 1: TFs.pdf  148 kB  Uploaded Thu Mar 18 08:02:52 2021  | Show | Show all
Attachment 2: PSD.pdf  180 kB  Uploaded Thu Mar 18 08:02:58 2021  | Show | Show all
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