Today afternoon, it was not possible to reach LN2 most probably due to the unbalance of the B1p 56 MHz upper and lower sidebands (see fig.1).
In the lock started at 18.11 UTC (when CARM NULL 1F has been achieved), we added -11 as MICH offset in order to overimpose the sidebands to proceed up to LN2, the trick worked (see fig.2) but the ITF unlocked at LN2 due to huge oscillation at ~55 Hz .
Thus, to save the weekend, we decided to reverse the last step of DAS WP.
So, at 19.24 UTC, we came back to STEP_1S (61729) .
| STEP_1S | CH [W] | INNER DAS [W] | OUTER DAS [W] | |
| W | on the ITF | 0.068 | 0.090 | 1.857 |
| on the pickoff | 0.418 | 0.0146 | 0.302 | |
| N | on the ITF | 0.091 | 0.266 | 2.972 |
| on the pickoff | 0.561 | 0.044 | 0.484 |
After that, the ITF achieved LN3 (at 20.25 UTC) without adding extra offsets (fig.3).
As requested by Romain, the BS TY SET was put to 0.
We left the ITF to Romain.
