J. Kissel,

Using the data gathered by Travis and Betsy last week (LHO aLOG 42149), I've tuned BRD S/Ns 013 and 004 to match the highest vertical (a.k.a bounce) and roll mode frequencies of the newly suspended H1 SUS ETMX. Results are attached and tabulated below:

    'Target [Hz]'    'BRD S/N'    'Mean Fit Freq. [Hz]'    '% Diff [%]'
    '9.697'          '004'        '9.69'                   '0.071'     
    ''               '013'        '9.685'                  '0.13'      
    ''               ''           ''                       ''          
    '13.775'         '004'        '13.812'                 '0.27'      
    ''               '013'        '13.73'                  '0.33' 

The uncertainty in the frequency corresponds to the original binwidth of the measured vibrometer / QPD data, +/-15 mHz.

Setup for measurement is as described in the HAM ISI TMDs (see LHO aLOG 38741) using corroborating evidence from both the laser vibrometer and a primitive shadow sensor setup. To calculate the above "Mean Fit Frequency," I used a least square's minimization with a Lorentzian seed function,
    fit(f) = (1/Q)^2 ./((f - f0).^2 + (1/Q)^2) + C 
to fit both sensors' data to obtain the measured frequency within the noise, and then took the mean of the two sensors' results.
The mean frequencies are less than 1% different from the target frequency of H1 SUS ETMX, which means the tuning is within requirements of "match target frequency to better than +/-1%."

I've left the tuned valentines on Betsy and Travis' desk.