The changes in environmental coupling with the change from 75W to 60W ( https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=70808 ) require that we re-measure some of the coupling functions that were measured in the pre-run set of PEM injections in May. Today I began those injections by injecting acoustically in the LVEA, as well as shaking HAM6 and the ITMY cryopump. I also set up for acoustic injections at EX.

In addition Sheila and I did some bias manipulation for ETMX. I injected currents onto the EX building ground and swept the ETMX bias as I had in January (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=67075). The figure shows that there has not been much change in the bias setting that minimizes grounding noise.