The steps that lead to success:
- First I got the best mode frequency estimate so far, from Keith Riles alog: 508.2892Hz (19190)
- Next I drove at a frequency nominally 1/10min above: 508.2892Hz + 1/(60sec*10) = 508.290867 Hz
- (Note: I picked a higher frequency because the neighbouring mode is at a lower frequency.)
- This produces a beat signal with a period of 13min, maybe +-10sec
- Thus, today our best mode frequency estimate is f0 +- df = 508.2892Hz + 1/(60sec*10) - 1/(60sec*13) +- df = 508.289585Hz +- 0.000017Hz.
- Thus, a simple awggui drive at that frequency should run away with at most 1/df/360deg = 167sec/deg, or 2.8min/deg
- I guessed an initial phase and left the drive running during the commissioning call, and got a nice decline of the mode.
- Next I designed a feed-back filter that matched my successful awggui drive (all fast enough that my feed-back phase didn’t run away.)
- That loop looked good so far - except that we several times tripped the silly hardware watchdogs - they take us out at about 1/2 of the DAC range... :-(

- We then turned on all violin damping filters. Notably this includes MODE5 on ETMY, which is a broadband filter also affecting the drive at 508.2896Hz.
- We will observe this state for a while before complete declaring success.

The filters currently used are FM1, FM4 and FM5 (a +12deg), and a gain of about +500.
The setting are not in Guardian yet.