This morning we changed the cabling of the QD photodiodes for the automatic alignment in order to be able to change the phases on the NF and the FF independently. We plugged on the NF quadrant the new one, and on the FF the one which used to be splitted into two until now.  We then asked B. Boom for the EIB rebalancing.

We tuned the phase of the FF by injecting a line at 2 Hz on MC tx and maximizing the FF signal, and the phase of the NF by injecting on IB tz and maximising the signal on the NF. However I made a mistake while injecting on MC tx, so that we'll have to check the tuning again.

We measured the new sensing matrix only with the BPC loop closed (Aa and RFC open) by injecting noise (a line at 2 Hz) on each Aa degree of freedom (GPS reported in the table below).

Once we computed it, we proceeded by iterations. To adjust the Aa error signal offsets we manually aligned the mode cleaner, we subtracted the offsets in the cfg file and we were then able to close the Aa in drift control and the RFC, and compute again the sensing matrix. 

We are now able to close the loop in full bandwidth, and as usual we can see an improvement on the RFC error signal (purple in drift control, blue in full bandwidth).