Ushiba, Yokozawa, Tanaka

This morning, we found that GRX could not be locked even though the flash amount seemed to be large enough (> 0.8 from the view of K1:LSC-TR_GRX_NORM_OUT_DQ ). According to the GRX PDH error signal channel (K1:ALS-X_PDH_MIXER_DAQ_OUT),  Any PDH-like signals seem to be not observed. However, since the DC power on the PD has some responce whenever GRX was flashed, the PD for PDH itself seems to be turned on. Also, CMS seems to be turned on because K1:ALS-X_PDH_MIXER_DAQ_OUT has some responses when we operated some switches on the CMS. So we suspected that the LO has something wrong.

Yokozawa-san and I entered mine and confirmed the LO and the CMS for PDH were turned on. Then, we checked whether the LO emitted the 33 MHz signal or not by using Moku:lab. However, we could not obsered any signal at 33 MHz. (This time, we confimed Moku:lab could be observed the output of GRY LO which emited the signal with the almost same amplitude at different frequencies.)

We tried to solve it by restarting the LO but the situation was not changed. After this, we found that the "UNLOCK" and "ERR" sign were shown on the display. we checked the error messages. There are many error messages (fig.1).

According to the manual, we need to ask the manufacturer to fix the LO in the case that their messages are shown. This afternoon, we will bring the other RF generator from Mozumi and try to solve this issue by replacing the LO.