Reports until 17:30, Tuesday 06 March 2012
H1 SEI
greg.grabeel@LIGO.ORG - posted 17:30, Tuesday 06 March 2012 - last comment - 15:26, Friday 09 March 2012(2369)
A tale of two pods

Pods #94 and #71 were experiencing the problems laid out in alogs 2308 and 2321. So today I de-podded both of them. During the de-podding I noticed no issues with the feet or any other kinematic devices.

I did find a broken flexure on #71, however (pictures attached). Which is odd since the GS-13 tested fine on arrival. Somewhere in between its arrival and testing it completely failed. It's possible it was severally fatigued during shipping and only recently failed.

Pod #94 has had its brains swapped with another failed GS-13 (mechanical issues) and will hopefully be tested sometime tomorrow to see if that solves the gain issues. If not that should point us toward some mechanical problem that I haven't seen before.

Both of these pods will become test pods (if their issues can be fixed) until they can be sent to LLO for retesting.

Images attached to this report
Comments related to this report
hugo.paris@LIGO.ORG - 15:26, Friday 09 March 2012 (2401)

A Huddle test was performed earlier this week in order to evaluate the effect of the reparations.

  • Pod #94 does not feature a gain of 1/2 anymore. It confirms that its pre-amp was initially malfunctionning.
  • Pod #71 does not output signal. It did output signal before having its flexure replaced. It is possible that an electronic mis-connection was caused during de-poding/repoding process.

Results and pictures of the test are attached.

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