Yesterday we made some measurements for the noise model (end sation PDH spectra and open loop), and ALS COMM slow path, fast path and open loop). 

Then we moved on to trying to make some noise measurements.  We tuned the demod phase of RF A 9 to put the signal in the Q phase (we don't have enough range with the phase shifter to put it in the I phase).  The demod is now on local control (remote controls not working) with al switches down except for 8, 2, 1, and 1/2 (11.5 ns delay). 

We also tried to check the IR alingment into the arm cavity by locking at the transmitted PD.  We found the 00 mode with the COMM PLL offset at 1.23, and saw up to 90 counts in transmission.  We saw a misalingment mode (between pitch and yaw) at 6.48, with 17 counts in transmission.  We strugged to improve this, mostly because the transmitted power was fluctuating so much from the frequency noise. 

We engaged the boost on the PLL readback path, (adding more DC gain to ALS CARM).  This reduced the noise significantly, although we were still moving by mre than a linewidth, so we can't really make a linear measurement when locked with ALS COMM.