Today the injection locking of the high power oscillator (HPO) was not as good prior to the water
leak on Wednesday.  We examined the overlap between the front end (FE) and the HPO and tweaked it.
The beam profile appeared to improve as a result.  The reference level for the injection locking
was altered from -1.20V to -1.30V.  The injection locking appeared more robust with this setting.
No relocks were encountered during the lunch break.

    Using the high power attenuator, the output of the HPO was reduced to ~29W as measured by the
water cooled Ophir power meter on the table.  The beam was aligned to the pre-modecleaner (PMC).
Initially the reflection locking photodiode output was:
  L02 position = 61 mm on rail, 10 on micrometer
  unlocked = 922 mV
    locked = 185 mV
  visibility = (unlocked - locked ) / (unlocked) = 79.9%
We moved the mode matching lens L02 towards the HPO.
- L02 position = 56 mm on rail
  unlocked = 917 mV
    locked = 95 mV
  visibility = 89.6%
- L02 position = 49 mm on rail (this is as far as we could move it because another mount was in
                                the way)
  unlocked = 907 mV
    locked = 95 mV
  visibility = 89.5%

~26W was measured after the IO EOM.  This value is consistent with the PMC visibility.

    The frequency servo was locked after a minor tweak to the vertical alignment of the beam.
~60 mW was incident on the reference cavity.

    Things are by no means optimised.  All servos were left running as a test.  Obviously both
the FE and HPO are running.  The relock counter was reset, the power watchdogs for both lasers
have been engaged.  Autolock for the frequency servo was left dis-engaged.

    The values for the PMC transmission reported on the MEDM screens are out of whack.  There
are a few other signals that need to be checked out too.

    We will crank up the power to the PMC next week.

 Should the laser(s) trip for some reason, do not attempt to resuscitate them! 


Jason, Peter