power before AOM :31.1mW
after single pass: 24.1mW 77% single pass effiicency
after double pass: 20.45mW 66% double pass efficiency
The beam position on the iris after the retro reflecting mirror has not changed.
I tuned the upper periscope mirror pitch, this brought the transmitted PD voltage back to 1 V.
We have 5.8 mW in the ALS path before the Faraday, 5.33 mW after the Faraday, 4.3mW going towards the fiber, and 1.04 mW going towards the fiber launch PD (external on the fiber dist box).
In this configuration, I measured ~3.1mW at the input of the ALS fiber distribution and 100uW at the MSR.
and the end station we see 40 uW coming out of the fiber, not really enough.