I began realigning the PRC probe beam (sent into HAM2 via IOT2R) to the PRM. First of all I aligned the beam reflected from PRM and transmitted through IM4 back into the aux laser path, using an iris, centering on lenses, and the FI aperture as a guide. This required some significant repositioning of the lower IOT2R periscope mirror, because this was adjusted in order to dump the IM4 trans beam recently for the benefit of the ISS photodiode. I then turned on the aux laser and overlapped the main beam (as best as possible just by looking at the spots on a card at two locations). With the main beam now coarsely overlapped with the aux beam, I aligned it to the RFPD that is used to generate the main laser / aux laser beat signal, maximizing the DC output of the PD. I observed the RF output on the HP spectrum analyzer, but wasn't able to see a beat signal (this might require more tuning of the aux laser temperature offset). One thing I did notice, however, were big peaks in the spectrum at the 9MHz and 45MHz sideband frequencies. These peaks remained when the aux laser was turned off. Since this beam is just the forward beam from the IMC, one would hope that the RF sidebands were pure phase modulation... is this an indication of unwanted RFAM in the IMC trans beam already? I don't know for sure what the IFO state was when I observed this, though I do know that the PRM was deliberately misaligned by this time.