I've been trying to lock the PLL for the AbsL Experiment but I can't see the beat (between the auxiliary NPRO and the PSL).

I believe the alignment of the PLL is not good. The Farady Isolator is definitely not perfectly aligned (you can see it from the beam spot after it) but still it should be enough to see something at the PLL PD.

it's probably just that the two beams don't overlap well enough on the photodiode. I'll work on that later on.

I'm leaving the lab now. I left the auxiliary NPRO on but I closed its shutter.

All the flipping mirrors are down.