Common Mode Servo Board

Document #:

LIGO-D040180-v5

Document type:

D - Drawings

Abstract:

Common Mode Board

Files in Document:

• D040180-v5.pdf (file is not accessible)

ICS/JIRA Record:

• ICS_LINK

Topics:

• Sensing and Control

Authors:

• Daniel Sigg

Notes and Changes:

This version (-v5) is a consequence of ECR E1400320 and is only required to account for reduced green light finesse as a consequence of high green light transmission of the initial ETM coatings. Note that this board has the following four types:
1) LL type: Arm Length Stabilization (ALS), Laser Locking
2) ALS type: Arm Length Stabilization (ALS), Cavity Locking
3) MC type: Input Mode Cleaner (IMC) Cavity Locking
4) CM type: Interferometer Common Mode
The component values for each type are given in E1200907. (Note that some, but not all, component value changes for each type are given in the D040180-v5 schematic).
The -v5 change only effects component value changes to the ALS type (aka ALS PDH board). There are two solutions (involving only component value changes) to the required filter change, both delineated in E1400320, and shown in D040180-v5 as mark-ups to sheet 6.

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This is a marked-up revision (aka 'red-lined', not incorporated into the source files). See -v4 for the source files.

Referenced by:

• LIGO-E1400320-v2: ECR, CM Board Modifications (green finesse)