Yeah, the cables are isolated and no inversion could happen.
| Quote: |
|
Are you sure that all the cables involved are isolated and there is no polarity inversion? e.g. The unfunctional combination provides HV to GND directry at the cable, for example.
|
Even more bizzarething is that it works now!  I'm not halucinating here but the same thing was not working before.I even have lab notes from yesterday when it wasn't working.
This is pretty bad as I don't want to be unaware of something in the lab that caused this. The only other clue here in all this is that the laser intensity changed. We control the intensity of light going into the experiment at (24,110) through the half waveplate before a PBS. Rana told me that the polarization direction of laser coming from NPRO shouldn't change, but since the incident of last Friday, I have had to change the rotation of this half waveplate in both directions to ensure same amound of light reaches the cavity as on North. since no alignment was changed at the south PMC, there is no reason for the mode matching to change drastically there or during the day. but this is the only fishy clue I've got for now.
Presently
Both cavities are locked. with same amount of gains in the FSS and PMC loops in both paths as before. The can's temperature as reached to the setpoint and the beatnote frequency PID is working to take it to 27.34 MHz. I'll set trigger for tonight for beatnote frequency noise measurement if the frequency reaches in the range of the photodiode.We then will know what is the impact on the experiment noise. |