Attached are plots of the pre-modecleaner, power stabilisation and frequency stabilisation servo
transfer functions as they were on Friday.

    I'm not sure what the dip at ~23kHz in the frequency stabilisation plot is but it might be
due to injection locking of the high power oscillator.

    The power stabilisation servo needs adjusting.  At the moment the displayed diffraction
levels are too high - it needs to be recalibrated.

    The pre-modecleaner servo is functional but also needs checking out.  Even with attenuating
the light on the locking photodiode, its output bursts into oscillation every now and then which
causes the pre-modecleaner to "blink".