Akutsu, Simon, Miyo
We added capacitor on the Satellite box(S1604897) for photo sensor to remove strange high coherent noise on all 4 channels.
- First, because there are high coherence between all photosensor in broad band, we guessed that these signal caused in the satellite box.
- The ASD of the 3 photosensors which are installed on the optical table in IYC chamber are shown in attached image. In this time, WAB is not released. All 3 sensors have good coherence in broad band. It must be caused in common source in somewhere
- Then We added capacitors (0.47uF) at the C101B each channels to lowpass the noise.
- After that, Photo sensor signal is getting better than before added.
We tried to measure the damping decay time to of the WAB suspension using coil magnet actuator attached on the WAB body ( ).
- We changed the burndy pin for coil magnet which register is 4 ohm which is totally 19.9 ( 4+4+12 ) ohm. Because yesterday we used 75 ohm which is totally 161.9 ( 75+75+12 ) ohm, current in the coil was not so much.
- After change 4 ohm burndy pin and change to more powerful power supply, we confirmed response of the fource injection with coil magnet actuator. ( )
- Raghly We can estimate decay time. I’ll estimate later.
We added capacitor on the Satellite box(S1604897) for photo sensor to remove strange high coherent noise on all 4 channels.
* First, because there are high coherence between all photosensor in broad band, we guessed that these signal caused in the satellite box or cable.
* The ASD of the 3 photosensors which are installed on the optical table in IYC chamber are shown in attached image. In this time, WAB is not released. All 3 sensors have good coherence in broad band. It must be caused in common source in somewhere
* Then We added capacitors (0.47uF) at the C101B each channels to lowpass the noise.
* After that, Photo sensor signal is getting better than before added.
We tried to measure the damping decay time to estimate Q value of the WAB suspension using coil magnet actuator attached on the WAB body ( ).
* We changed the burndy pin for coil magnet which register is 4 ohm which is totally 19.9 ( 4+4+12 ) ohm. Because yesterday we used 75 ohm which is totally 161.9 ( 75+75+12 ) ohm, current in the coil was not so much.
* After change 4 ohm burndy pin and change to more powerful power supply, we confirmed response of the fource injection with coil magnet actuator. ( )
* Raghly We can estimate decay time. I’ll estimate later.
