Daniel, Terry, Nutsinee

Yesterday we installed a PFD to (phase) lock our 158MHz VCO with the beat note (alog44135). As the result we now have a frequency correction signal to send to OPO PZT. This signal comes out of Dual Dsub Patch Panel (third from the left), goes through a 10Hz lowpass blue box (with gain of -10), and into in-vac PZT driver. In addition Terry also swapped the fibers from PSL at ISCT6 feed through after realizing that it was plugged in wrong (from the PSL end I think) so that the PSL that's used for beat note is 158MHz shifted coming in and the PSL LO has been down shifted (0Hz) coming in (which would be the same as what goes into the IFO). We also put back the motorized half waveplate we borrowed from the PSL beat note path. 

Next thing to do is to include feed forward from IMC VCO in the frequency locking loop. Once that's done we should be ready for 3MHz hand-off.