For both PMC locking and injection locking, servo board and field box board were modified as per FRS 6500 (FRS id=6500 and alog 31047).
After the modified boards went in, we removed the 20dB attenuator on the PSL rack RF patch panel for 35.5MHz for PSL EOM.
This seems bump up the ILS and PMC length locking optical gain by about a factor of 10 (for ILS the analog gain was changed to compensate).
We also remeasured the demod phase for ILS and PMC length locking. For ILS we didn't see much change (1ns), but PMC was significant, we ended up changing 3ns, i.e. 39 degrees for 35.5MHz.
Demod setting are shown in the first two pictures, ILS (first attachment) and PMC (second). Third picture shows that the ILS is on the left bottom of the four delay lines, and PMC is on the right bottom.
The fourth picture shows the OLTF of PMC that is pretty close to the one we have now. Note that UGF is much much higher than before simply because of the optical gain and the demod phase (might have to change).
Unfortunately the floppy for SR785 failed, so we'll remeasure the ILS loop gain again tomorrow.
Here are the spectra of HVMons and Mixer_out, both in counts at the input and in calibrated in Volts.
J. Kissel, for M. Evans, D. Sigg, K. Kawabe With these electronics changes comes new compensation filters scattered throughout the PMC model, which has resulted in SDF differences. The following filter banks now have new filters that have been accepted into the SDF system as ON: H1:PSL-PMC_INOFFSET_CALI FM3 "LP1" zpk([],[1],1,"n") H1:PSL-PMC_MIXER FM2 "aWhite" gain(-0.005) H1:PSL-ILS_MIXER FM2 "aWhite" gain(-0.005) H1:PSL-ILS_HV_MON FM10 "aWhite" zpk([100],[1],-1,"n")
