[Marc, Michael, Yuhang]

As reported in previous elog (eg 3189), the error signal of GRMC is about 10 times smaller than the nominal value.

We checked the RF signal used to lock about found that it is about -36dBm.

So we decided to use an unused amplifer from the amplifier rack (previously used for EOM FC/GRMC and providing 20.8 dB amplification).

After that, our RF signal is about -9dBm.

With this higher RF power, the error signal is now 800Vpk and we can lock GRMC and MZ with no particular issue.

The GRMC transmission with MZ offset of 4.2V is now about 26mW (25mW nominal).