Today I adjusted the PSL pump diode operating currents to attempt to improve PMC Trans while maintaining output power.  PMC Trans has been dropping and PMC Refl increasing, and alignment tweaks have not been yielding much improvement; suspect the cause is mode matching changes due to the natural decay of the pump laser diodes.  With the ISS OFF I tried several different combinations, but the best was found by asymmetrically pumping both amplifiers slightly; the attachment shows the various steps and how they changed PMC Refl and Trans.  I ended up with the following current setpoints (actual current is slightly lower, as seen in the attached trends): PS1 at 9.1A, PS2 at 8.9A, PS3 at 8.9A, and PS4 at 8.8A (PS1 and PS2 supply the Amp1 pump diodes, PS3 and PS4 supply the Amp2 pump diodes).  When I re-engaged the ISS I had to adjust the RefSignal from -1.94V to -1.95V to account for the slightly increased power transmitted by the PMC.  PMC Trans is currently ~109.0 W and PMC Refl is currently ~16.8 W.  Will continue to monitor this.

This closes WP 11806.