(0) IFO to DOWN. IMC to OFFLINE.


(1) Unlock FSS,
    Sitemap > PSL > FSS "LOOP AUTOMATION" in the middle, hit the red OFF button.
        H1:PSL-FSS_AUTOLOCK_ON set to 0.0.
        DONE via command line. Took ~10 seconds to take affect.
        *also* hit the AUTOLOCK OFF button, because that *didn't* change when I caput the command line variable.
          
        
    If that doesn't work, go to bottom right corner of FSS overview, to MANUAL subscreen button
        hit red "OFF" button in the upper left "LOOP" block.
        H1:PSL-FSS_LOOP_MODE (0.0 when locked... dunno the number when unlocked/OFF is requested)
        
    (didn't do this.)
        
PDT: 2023-10-31 08:09:21.078402 PDT
UTC: 2023-10-31 15:09:21.078402 UTC
GPS: 1382800179.078402
        
(2) Unlock ISS,
    Sitemap > PSL > ISS "AUTOLOCK" hit the gray OFF button
        H1:PSL-ISS_AUTOLOCK_ON set to 0.0
        
    If that doesn't work, got to "Manual Mode" subscreen, and hit red OFF button
        H1:PSL-ISS_LOOP_STATE_REQUEST (0.0 when locked... dunno the number when unlocked/OFF is requested)
        
    Step (1) automatically turns off the ISS.
        
(3) Unlock PMC,
    Sitemap > PSL > PMC "LOGIG CONTROL" > middle of the screen "LOCK", hit red OFF button.
        H1:PSL-PMC_LOCK_ON (-30000 when locked... dunno the number when unlocked/OFF is requested)
        
    Keep PMC screen open.
        
(4) Turn off uncontrolled ramp
    PMC > "LOGIG CONTROL" > middle of the screen "RAMP," hit the red OFF button.
    
    # Forgot to do this at the start, and saw a lot of "extra peaks" in the H1:PSL-PWR_PMC_TRANS_IN_IN1 time series
    # Only noticed after I took the DTT full bandwidth measurement of the transmission.
    # But, for all the production data, I did turn this OFF.
    # caput H1:PSL-PMC_RAMP_ON 0.0 should be equivalent.
    
    # H1:PSL-PMC_RAMP_ON is -30000 when "normal"
    
(5) Turn on input for controlled ramp
    H1:PSL-PMC_TF_IN_SW2 is 0.0 when OFF (probably 1.0 when ON)
    
    # H1:PSL-PMC_TF_IN_SWSTAT is 34304 when "normal"
    # H1:PSL-PMC_TF_IN_SWSTAT is 38400 when the user-controlled ramp input switch is ON
    
(6) Adjust the ramp rate and ramp voltage range as desired:
    
    H1:PSL-PMC_ALIGNRAMP_FREQ
    H1:PSL-PMC_ALIGNRAMP_MIN   (volts)
    H1:PSL-PMC_ALIGNRAMP_MAX   (volts)
assume that the upper and lower limit is 10V.

    Current value for the ramp rate is 0.1 Hz. Might be interested in 1 Hz or 10 Hz.
    Need to look up PMC cavity parameters (length and cavity pole frequency).
    
From T0900616:
    L (roundtrip) = 2.02 m (2.02 m ± 0.008 m)
    Finesse = 124.708 (124.536 ± 5.091)   120.44 ± 0.6
    FWHM = 1.19 MHz (1.195 MHz± 0.0488 MHz)  1.19 MHz± 0.06 MHz 
    Free Spectral Range = 148.532 MHz ± 0.585 MHz   148.32 MHz ± 0.742 MHz
    
    Current ramp voltage range is MIN = -7, MAX = +7 [V].
    
    The channel that records the instantaneous value of the ramp is 
       H1:PSL-PMC_TF_IN_INMON 
       H1:PSL-PMC_TF_IN_IN1   ## THIS IS THE CHANNEL I USED
       
       Also, maybe H1:PSL-PMC_TF_A_OUTPUT

During the sweep, watch (via ndscope):

(7) Grab transmitted power PDs on ndscope to look for FSRs.
    (A) see "PD04" on the M16 > M17 > M18 > M19 > L15 path.
        H1:PSL-PWR_PMC_TRANS_INMON
        In nominal low noise, the if the input is 10872 [ct] (OUT is 109.03 W)
    (B) ISS_PDA and ISS_PDB on the M29 > M30 > ISS_WP > ISS_TFP > ISS_L > ISS_BS1 > ISS_BS2 path
        H1:PSL-ISS_PDA_INMON 
        In nominal low noise, the ~3000 +/- 100 [ct]
            there is a "calibration" filter, but unclear into what units.
            In nominal low noise the OUT is 1.84.
        (can use PDB, since the PMC and ISS is unlocked, but having two uncalibrated powers at two ports should be plenty enough to get what you need -- which is "what's the voltage 'distance' between the largest peaks")
        
        
    ## Without the PMC locked, H1:PSL-ISS_PDA_INMON or IN1 "looked really noisy," so I went with using H1:PSL-PWR_PMC_TRANS_INMON or IN1 for the whole study.
       
Once you're happy finding FSRs,
Use DTT to grab a live time series of
    H1:PSL-PWR_PMC_TRANS_IN1 
    H1:PSL-ISS_PDA_IN1     ## Again -- didn't use this.
    H1:PSL-PMC_TF_IN_IN1
since none of these are stored in the frames.

Don't use the output of the H1:PSL-PWR_PMC_TRANS filter:

    - FM1 "lp" filter and gain in H1:PSL-PWR_PMC_TRANS banks are convenience, not physics or compensation. FM1 single pole, f_p = 0.15 Hz, is to low-pass out the "noise" on the signal such that the EPICs OUTPUT is stable / quiet for trending.
    - GAIN of 0.01 is a rough calibration into Watts of power on the PD.
    
Don't use the output of the H1:PSL-ISS_PDA filter:
    - Unclear what the FM1 "calibration" filter is (whether it's W or something else). Nominal value is 
    - also, there's *another* filter downstream, H1:PSL-ISS_PDA_CALI_DC which has an additional "cali-mean" filter...
          In nominal low noise, the input is +1.84+/-0.02 and the output is +9.059