J. Kissel, F. Clara
ECR E2400330

Fil modified another UK SatAmp (D0900900 / D0901284) per ECR E2400330, which means "rev'ing" up the D0901284 circuit board inside from -v4 to -v5.

However, this one, S1000278, seems to have more variability in components that were not changed between channels -- namely if I 
    - fit the measured zero and pole frequency, and 
    - assume that a perfect, as drawn, value for the R181 = R182 resistors (as Fil confirms that these were +/-0.1% resistors)
the total capacitance seems to have a ~2% variability. 

Not unreasonable, given that typical off-the-shelf caps of value 10 [uF] have +/-10% variability, so with two of these caps parallel, you could expect the total capacitance to be between 18 and 22 [uF], or +/-10%.

As such, I propose we set a tolerance for these transfer functions to have the following values at the following "check" frequencies (i.e. logspace(log10(5),log10(50),3), which is a requestable frequency vector on an SR785 frequency response sweep, if fstart = 50, and fstop = 0.5, with N points = 3). These assume values assume 1% variation in transimpedance amp feedback resistor, and 2.5% variation in whitening cap.

    Freq    Mag (Upper Bound)    Mag (Lower Bound)    Phase (Upper Bound)   Phase (Lower Bound)  
    [Hz]    [V/V] or dB([V/V])  [V/V] or dB([V/V])          [deg]               [deg]

    0.5      5.4098 or 14.664       5.0554 or 14.075      -106.23             -106.5

    5.0     38.415  or 31.69       36.671  or 31.286      -135.09             -133.72

    50.     54.987  or 34.805      53.868  or 34.627      -174.2              -173.9

    Freq    Mag Tolerance              db(Mag Tolerance)          Phase Tolerance 
    [Hz]    [V/V] +/- [V/V]         dB([V/V]) +/- dB([V/V])     [deg]  +/-   [deg]

    0.5      5.2313 +/- 0.17847       14.372 +/- 0.29138      -106.36  +/-  0.12754

    5.0     37.547  +/- 0.86844       31.491 +/- 0.19861      -134.41  +/-  0.67952

    50.     54.428  +/- 0.55902       34.716 +/- 0.088757     -174.05  +/-  0.14395

That being said, we wouldn't replace the non-ECR components if the SatAmp didn't pass this test, we'll just use those under-performing SatAmps to be used on low priority stages, i.e. ones not used for damping loop control, i.e. not top mass stages. If many end up exceeding this thresholds, then we can start to prioritize which suspensions get the best.