This morning, I started taking transfer function measurements on the two new Tip Tilt suspensions (JM1 and JM3 for JAC) recently installed in HAM1 chamber. The screenshots are attached below - the chamber has a strong purge air flowing which created a noisy environment and I had to drive the suspensions really hard get a decent coherence. Travis dialed the purge air down, which helped (however, there were other ongoing LVEA work which were kind of saturating the DAC).

This is first of the many measurements to be taken (including osem spectra etc.), however JM1 looks great - ignore the magnitude for now and we will sort it out in the new year. The resonance peaks are where they should be - especially for JM1, just like how I tested it in the triples lab.

Similarly, JM3 is also behaving like how it was in the lab (RyanC took that measurement in the triples lab) -   couple of peaks on L and P dof are off by 0.15 Hz (due to longer wires, not much control here). Y dof has cross coupling from L dof at 1.25Hz, but if you look at this damped TF (when L and P damping were kept on) plot - the cross coupling is gone.  

More tests are in the pipeline and better results are expected, however this is a decent start.

The templates are stored at the following locations,

JM1

/ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/JM1/SAGM1/Data/

2025-12-19_1820_H1SUSJM1_M1_WhiteNoise_L_0p02to50Hz.xml
2025-12-19_1820_H1SUSJM1_M1_WhiteNoise_P_0p02to50Hz.xml
2025-12-19_1820_H1SUSJM1_M1_WhiteNoise_Y_0p02to50Hz.xml

JM3

/ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/JM3/SAGM1/Data/

2025-12-19_2100_H1SUSJM3_M1_WhiteNoise_L_0p02to50Hz.xml
2025-12-19_2100_H1SUSJM3_M1_WhiteNoise_P_0p02to50Hz.xml
2025-12-19_2100_H1SUSJM3_M1_WhiteNoise_Y_0p02to50Hz.xml

 2025-12-19_2100_H1SUSJM3_M1_WhiteNoise_Y_0p02to50HzDampingON_LP.xml   - L and P dof damping ON during the measurement.

Purge air in HAM1 was set to its nominal flow once the measurements were complete.