I've been trying to lock the laser to the PMC since we adjusted the Faraday. It's basically badly out of alignment now. I can only see very higher order modes flash when I scan the cavity.
The problem, currently, is that the Faraday is too high and we don't have enough mirrors to control the beam going through it. I'm going to install a second mirror in a bow-tie configuration tomorrow and realign the beam through the Faraday, 21.5MHz EOM and, hopefully, the PMC.
I also spent a lot of today tracing out the control loop for the laser slow control. Once I have all the control loops understood, I'm going to draw a diagram for the Wiki.
P.S. Found out that the PSL PMC Servo board is D980352. I've updated the Electronics page on the Wiki to indicate this...