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Revision 7 as of 2010-08-08 05:11:05
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 . The FSS has a [[PSL/Frequency Stabilization Servo/SLOW PID servo|/SLOW PID servo]] which offloads the FAST (PZT) path by feeding back to the NPRO's SLOW input. The FAST has a rough calibration of 5 MHz/V while the SLOW is more like 5000 MHz/V. It has a ~0.1 Hz pole and so that's why its called ''SLOW''.

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== List of FSS Related Electronics Schematics ==
 * [http://www.ligo.caltech.edu/docs/D/D040105-A/D040105-A.pdf TT FSS Box] (by Schwinberg, Myers, and Savage, based on the Rich Abbott original)
 * TT ISS Box (by Flavio Nocera w/ lots of prodding from Rana)
 * [http://www.ligo.caltech.edu/docs/D/D980401-B1.pdf VCO Driver Box] (R. Abbott)
 * FSS RFPD (old LSC kind by Dale Ouimette)

 * Variac on the HEPA (D. Busby's handiwork)

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 . '''Test Results for The New TTFSS'''

 * [https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=20783 Test Plan](Cervantes, Schwinberg, Savage)

 * [https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=22273 Test Result box #6] (Chalermsongsak, Arai)

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The FSS has a [[/SLOW PID servo]] which offloads the FAST (PZT) path by feeding back to the NPRO's SLOW input. The FAST has a rough calibration of 5 MHz/V while the SLOW is more like 5000 MHz/V. It has a ~0.1 Hz pole and so that's why its called ''SLOW''.
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== List of FSS Related Electronics Schematics ==
Line 19: Line 34:
 * TT FSS Box (by Schwinberg, Myers, and Savage, based on the Rich Abbott original)
 * TT ISS Box (by Flavio Nocera w/ lots of prodding from Rana)
 * VCO Driver Box (R. Abbott)
 * FSS RFPD (old LSC kind by Dale Ouimette)

 * PMC 35.5 MHz Frequency Reference Card (R. Abbott)
 * PMC Servo (by Karwoski, based on the R. Abbott original - modified by Rana/Jenne based on the Hartmut mods)
 * PMC RFPD (old LSC kind by Dale Ouimette)
 * Variac on the HEPA (D. Busby's handiwork)
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The FSS stabilizes the fluctuations in the laser frequency by comparing it to a quiet Reference Cavity. The light is picked off just before it goes into the Pre Mode Cleaner, sent through a EOM and the frequency shifting AOM and then into the RC.

The FSS actuates on the NPRO Piezo (called the FAST path) and on a phase correcting Pockels cell (which is faster than the FAST path).


  • To lock:

Run the FSSAutolock script from the C1PSL_FSS screen (under the yellow ! button).


  • The FSS has a /SLOW PID servo which offloads the FAST (PZT) path by feeding back to the NPRO's SLOW input. The FAST has a rough calibration of 5 MHz/V while the SLOW is more like 5000 MHz/V. It has a ~0.1 Hz pole and so that's why its called SLOW.




See also PSL.

attachment:C1PSL_FSS.png


References

PSL/Frequency_Stabilization_Servo (last edited 2020-03-03 01:44:19 by YehonathandroriATligoDOTorg)