I investigated the status of the cabling for the IMC suspensions. The actuator coils for the MCi and MCe suspensions were cabled using the BNC feedthrough and the BNC-Dsub converter. The actuator coils for the MCo suspension were cabled using the Dsub feedthrough without the BNC-Dsub converter. I checked the resistance between the outer shell of the BNC connector and the chamber at the feedthrough in both cases of the BNC cables connected to the feedthrough and disconnected from the feedthrough.
| MCi | Connected [Ω] | Disconnected [Ω] |
| H1 | 24.2 | 46.6 |
| H2 | 24.6 | 47.6 |
| H3 | 20.4 | 47.5 |
| H4 | 24.3 | 33.6 |
| MCe | Connected [Ω] | Disconnected [Ω] |
| H1 | 37.7 | 58.1 |
| H2 | 38.0 | 58.2 |
| H3 | 38.4 | 58.6 |
| H4 | 38.5 | 57.8 |
For reference, I checked the resistance between pin#6/7/8/9 and the chamber at the feedthrough in the case of the Dsub cable disconnected from the feedthrough.
| MCo | Connected [Ω] | Disconnected [Ω] |
| H1 | - | 48.2 |
| H2 | - | 51.2 |
| H3 | - | 45.6 |
| H4 | - | 64.8 |
The results show the output impedance of the differential coil driver. The outer shells of the BNC connectors were not grounded.
