Beat note is still not under control. Its drifting at 10 kHz/min, too much for a lower range marconi measurement.

We would like to bring the frequency down from ~140 MHz  to something closer to 27.34 MHz  of Koji's resonant BN detector.  I'm going to try to use the relay auto locker feature of the PIDLocker_beta.py script again to get the BN to converge on some steady value (see PSL:2142). In the past the relay method was able to actually get a convergence to a BN value but failed to give good values as there was a thing with the cycle limit converging to zero in the case of these really slow BN thermal controls.  I suspect this was due to a relay step that was too small, the asymmetry of the heater actuation and/or large time lag caused issues.

For now I'll leave the relay on overnight to see if we are able to get a good convergence with a relay step of 0.1 W about mean heater power of 0.77320 W and common power offset of 0.48710 W.  The setpoint was left at 100 MHz, we will step it down to the 27.43 MHz gradually so as not to overshoot the BN past 0 Hz and flip the direction of the frequency.

The service running the PIDLocker_beta.py script for the cavity slow heater controls was stopped and was then manually restarted in a tmux session on ws1 using the following command:

> python PIDLocker_beta.py PIDConfig_CAVHeater.ini --autotune -d 0.1 -o 0.7732 -t 86400 -e

This should run the relay mode of the auto locker for 24 hours (86400 s) about a mean of 0.7732 W and a relay step of 0.1 W (bigger than in previous tests).  We'll see how it goes and reassess tomorrow morning.