Since phase 3a ETMX reaction chain transfer functions from thursday night didn't look good, Travis and Betsy went back in chamber on friday and moved back one of the top mass earthquake stop (one blocking the vertical direction). New series of transfer functions have been ran over the week end and are plotted in the attachments.

They now show a good match with the model and LLO measurements and moving the EQ stop definitely improved the results. Although, transverse still doesn't have any coherence with the drive, see second page of 2013-10-18[...].pdf attached

I checked the voltage at the output of the coil driver during the drive of transverse and the signal is clearly there, see image attached.

The attached results are described below :

(1) 2013-10-18[...] = Plot comparing R0 undamped TF phase 3a and the model

(2) allquads_[...] = Comparison between LHO R0 undamped TF phase 3a on friday night (2013-10-18), LHO R0 undamped TF phase 3a on thursday night (2013-10-18)

(3) Image = Screenshot of the drive signal of side osem at gps = 1066192865 (during transverse excitation) at (in red) the excitation test point, and (in blue) the coil driver output. Signals are coherent, meaning the chain between the dac and the coil driver is not broken