Started going through the list of tests from G2601523 to find/reduce the CRS noise.

Dark test (i.e. turning off the CRS laser)

• Added offsets matching the raw PD inputs when the laser was on (1S: -1307, 1C: -374.22, 1M: -2813.2, 2S: -1243.43, 2C: -2309, 2M: -113.725) in order to make sure the atan function gave back real data.
• The laser was off and the offsets were added at 10:35 PST (1470072968.0) 
• Took about 1 hour of data for spectra
• From my understanding, it looks like the dark noise/ADC might be limiting at the higher frequencies (>5Hz), but doesn't really account for much below ~5Hz. (Spectra attached, purple and oragne is dark, blue+green reference)
• dtt template saved in /ligo/svncommon/SeiSVN/seismic/HAM-ISI/H1/HAM3/CRS/Templates/dtt/CRS_HoQI_Dark_spectra_26-8-06.xml

Unplug HoQIs to get ADC Noise

• Unplugged HoQI's from pre-amp, kept same offsets from dark test (above) at 11:46 PST (1470077241.5) 
• Similar results as with the laser turned off (Spectra attached, red and black line is unplugged)
• dtt template saved in /ligo/svncommon/SeiSVN/seismic/HAM-ISI/H1/HAM3/CRS/Templates/dtt/CRS_HoQI_Unplugged_spectra_26-8-06.xml

Next steps are to add some copper on top of the laser to see if that reduces the noise, and then looking at the impact of the motion of the out of vacuum fiber once the LVEA is safe. The HoQI's will be re-connected to the pre-amp and laser turned back on so Jim can take some more transfer functions.