40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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Message ID: 1173     Entry time: Wed Dec 3 15:43:15 2014
Author: Dmass 
Type: Noise Hunting 
Category: Meetings 
Subject: Meeting notes 

ISS - what Koji has done with ISS/FSS would be good to copy - sum in DC offset at end of ISS box -

Stefan - input to last stage - change + pin to offset

Check out Nic's old elog after recp't of NEOS drivers - want [ V_rf / V_aud ]

Noise to back of AOM driver (SR785 -> SR560), measure RIN, measure beat, see beat increase


Check out Evan's median subtraction algo (to estimate coupling of RIN) - this takes median of spectra


RIN on transmission - coherent or not?

ND filter before PBS - increase power by X, decrease using ND filter


Isolators good? These are untested-ish - do we want translation stages for these?

Coherent white noise added into error point?

High freq noise at monitor PDs + low PD bandwidth (what PDs are we using / do we see the high RIN on the beat PD)?

Birefringence in coatings leading to multiple peaks with overlapping PDH error signals?


Get FTB-1-1 minicircuits transformers - skip RF grounding for now


New PLL scheme - mix beat down into low band

Zurich PLL?

Other servo boxes if no zurich: Old uPDH box? PDHv1? Misc NIM servo boards?

AD829 xover with SR560 for PLL?


PLOT Look at PLL RMS when beat, make PLL rms go down

ELOG V3.1.3-