J. Kissel

Taking the data from this morning's aLOG as my target frequencies, I've tuned BRD S/Ns 015 and 016 to match the highest vertical (a.k.a bounce) and roll mode frequencies of the newly suspended H1 SUS ITMX. Results are attached and tabulated below:

    'Target [Hz]'    'BRD S/N'    'Mean Fit Freq. [Hz]'    '% Diff [%]'
    '9.806'          '015'        '9.853'                  '0.49'      
    ''               '016'        '9.812'                  '0.066'     
    ''               ''           ''                       ''          
    '13.927'         '015'        '14.033'                 '0.76'      
    ''               '016'        '13.926'                 '0.009'

Setup for measurement is as described in the HAM ISI TMDs (see 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 with the noise, and then took the mean of the two sensors' results.
    
Betsy and Travis are installing these BRDs as I type.