Sheila, Haocun
We switched back to 36MHz demodulation first (with Gain=33), but there was still an offset for Yaw between the REFL loops and POP loops.
Then we chose to use 45MHz demod and adjusted the phases to put the SRM into Q phase (figures attached). We used -0.1 for Pitch (POP X_Q) and +0.1 for Yaw (POP X_I) in the input matrix, taking the measurements for gain and increased the power. It remained stable till 38W.
Evan, Sheila, Ed
As Haocun wrote, the POP X WFS seem to be working well, and we can now stay locked even when the recycling gain drops as low as 29.
We have been sitting at 30 and 35 Watts for about 20 minutes before losing lock due to something that looks like it could be a loop instability. We have been measuring loops and adjusting to try to make things more stable:
PRC2 P gain reduced by 6dB (in input matrix) to give a UGF just above 1 Hz. (in guardian, tested several times)
DHARD Y gain increased from 15 to 30 to give upper ugf of 4 Hz (works at 17 and 35 Watts, should not work at 2 Watts, in guardian)
CHARD Y gain increased from 50 to 70 to give upper ugf of 5.5 Hz. (worked once at 2 Watts and once 30 Watts, in guardian)
For DHARD P we edited the boost filters. (4th screenshot shows the new boost which replaced the old boostLTE and MSboost, but not 23Wboost) This is fine for 2 Watts and lock acquisition and is in guardian, but we haven't tested it at higher powers, so we will need to measure and check this before powering up.
To do tomorow to finish checking all hard loops:
check on DHARD P at 30 Watts, check CHARD P. We need to move the "final boosts" in the guardian so that they will come on when we reach 20 Watts, no matter what the request is.
As is the guardian should be fine for getting to 25-30 Watts.
