I came over to address the FSS issues and found that the laser had shut down at around noon (I would have hoped that the operator would notify me, but maybe he/she didn't notice it).

Seems that the NPRO tripped (again!).

Got the laser back on line, then started working on the FSS.

It appears that something is not right with the database.  0.1 unit changes on the FSS Common gain result in 4 dB gain changes - way too much.

I went back to two delay units (left and right) in series to get the loop locking (24 nsec on the left unit and 14 nsec on the right unit).

With gains at 0.8/0.3 (Common/Fast) the UGF is near 350 kHz with about 50 deg of phase margin.

Auto lock is working with threshold set at 0.2.

I will let it run over the weekend and investigate further next week.