Recovery of GRX lock and RF_LOCKED was achieved

Date: 2025/10/30

Members: Takaaki Yokozawa, Dan Chen

Summary

The repaired VCO circuit for GRX was reinstalled in the original configuration. After reinstallation, we tried locking the Xarm and successfully reached the ALS_LOCKED state. Then, we performed the initial alignment, and the interferometer recovered to the RF_LOCKED state.

Details

We installed the repaired VCO circuit for GRX and confirmed that Xarm could reach ALS_LOCKED.
Then, after completing the initial alignment, we requested RF_LOCKED from the center area and returned to Mozumi.
However, we found that PLLY could not be locked. So, during the PLL-Y locking process, we changed TEMPY_BIAS (K1:ALS-Y_LASER_TEMP_BIAS_OFFSET) from -0.50 to -0.44, and it successfully locked after this adjustment.
After that IFO could achieve RF_LOCKED state.