[EricQ, Jenne]

A few more details on our work for the evening, of switching the PRFPMI completely to IR signals (although still with a pretty big CARM offset).

We did the same transition for CARM to 1/sqrt(trans) signals, as last night (elog 9793).  The only difference is that for CARM actuation, we were using a -1*MC in the output matrix, rather than +1's for both ETMs. 

We then had a look at the relative sign and gain between the ALS DARM signals, and AS55Q, using a calibration line in DARM.  Before doing so, we used the DARM line (521.3 Hz, 50 counts) to rotate the AS 55 phase from -60.7 degrees to -97.7 degrees, which gave us about 20dB separation between the I and Q signals.  This informed us that we needed a factor of about 400 less gain for AS55Q than for the ALS darm signal, as well as a minus sign, so I put -400 in the DC normalization place in the LSC for AS55, so that my input matrix would go from ALSY-ALSX (1's) to +1 in AS55Q. 

This transition to AS55 was very easy, and once we did it, we held lock for 5 or 10 minutes, until a large earthquake from Papa New Guinea hit us.  Note however, that we still had a large CARM offset, and our TRX and TRY signals were about 0.1 counts, when we expect several hundred at perfect resonance. 

After that, we relocked, made both CARM and DARM transitions again, and tried to look at a CARM calibration line to see if we see CARM information in any of the REFL RF signals.  We lost lock after a few minutes (so, not related to our calibration line), so we didn't finish, but it looks like REFL55I, normalized by TRX+TRY is the most promising.  Also, REFL55's phase was already very good, while REFL11's phase was not. 

There were some moderate changes to the LSC model that happened, and matching screen changes.  I put in a switch just before the input triggering place of the CARM servo.  This allows us to switch from the "regular" input matrix, and a CESAR signal.  The inputs to the CESAR block are sqrtinv(TRX), sqrtinv(TRY), ALSX, ALSY and the output of the CARM row of the input matrix (so that we can have dynamic normalization of the RF signals).  I have exposed all of these changes in the input matrix screens.

I also modified slightly the ALS watch scripts, to include CARM and DARM servo filter watching, so now we can use the actual CARM and DARM servos.  We should make restore configure scripts for these!

The 2 gps times for when we made the transition from ALS DARM to AS55 DARM were 1081238160 and 1081240217.  We want to go back tomorrow, and extract some nice time series.

Here's a spectrum though, of the difference in noise between DARM on ALS, and DARM on AS55.  The CARM was always on 1/sqrt(Trans) signals during these spectra.  We have an enormous gain in high frequency noise performance once we switch to the RF signal, which is great.