jeffrey.bartlett@LIGO.ORG - posted 11:54, Wednesday 04 November 2015 - last comment - 12:13, Wednesday 04 November 2015(23107)
RF45 Noise Return
After relocking this morning the RF45 noise has come back, at a rate of several time per minute. This is knocking the range down into the high teens and low 20s Mpc. Confer with Evan, Keita, Mike, Daniel, and Filiberto. Set the intent bit to Commissioning while Evan & Filiberto are in the LVEA checking cabling.
Fil and I went to the ISC rack and started tapping the 45 MHz cable that comes out of the patch panel. As noted before, this cable is extremely microphonic. Tapping on the coiled-up portion produces huge burps in the EOM driver control signal.
We added some extra velcro around the coil, and then fixed the coil to the rack with some zip ties.
However, now that we have relocked it seems that this does not improve the situation.