R&D (FilterCavity)
NaokiAritomi - 17:00, Saturday 13 July 2019 (1472)
Trial of DC balance of homodyne
 
I'm trying to recover the DC balance of homodyne. Current situation is as follows.
 
without lens PD1: 2.96V, PD2: -3.04V, DC output of homodyne: -127mV
with lens: PD1: 5.28V, PD2: -5.02V, DC output of homodyne: 146mV
 
Now DC balance is not good. We'll continue this next week.
 
During this work, I accidentally dropped lens for PD2 of homodyne. Although the lens is inside lens holder and seems fine, it might cause some problem.
 
 
Now DC balance is not good. We'll continue this next week.
Comments related to this report
YuhangZhao - 15:00, Wednesday 17 July 2019 (1477)

I checked the current assumption as suggested by Matteo. It is fine. The situation now is the same with entry 1426. At the same time, for -19V channel, the current assumption is 0.063A. Although we don't have reference for this negative channel, I think it is also fine.