Reports until 16:02, Monday 22 July 2013
H1 ISC
sheila.dwyer@LIGO.ORG - posted 16:02, Monday 22 July 2013 (7158)
green PDH IQ plot
Alexa Sheila Stefan

The I mon of the demod was not broken; I was using a bad cable to look at it.  Now we are using the original demod again, using the I output, and the I mon and Q mon are on the scope visible from the ceiling camera (Imon is the x axis, Q mon is Y, both 500mV/div)

We have the phase shifter still on external (remote controlled); the phase we are using now is 107.82 degrees and on the servo board IN1 polarity is negative.  

Right now we are locked with a gain of -8dB, and a screen shot of the IQ polar plot is attached.  There is a lot of noise in I.  







Images attached to this report