aLIGO LHO Logbook

H1 IOO

stefan.ballmer@LIGO.ORG - posted 20:06, Tuesday 16 July 2013 - last comment - 09:55, Wednesday 17 July 2013(7107)

Bad RF cable

Just before the laser went dark, we discovered that the demod phases of both IMC length and WFS diodes had moved significantly, with all the signal ending up in the Q phase.

We found a bad connector on spigot 4 of the RF distribution panel, going to the EOM. Wriggling te cable resulted in ~30deg of phase shift.

The connector should be replaced tomorrow.

Comments related to this report

filiberto.clara@LIGO.ORG - 09:55, Wednesday 17 July 2013 (7113)

Link

Looked at cable in question with kiwamu. Did visual inspection, reconnected cable and looked at signal. Moved cable around, could not reproduce faulty connection as seen earlier.