We investigated the ITMY ULCOIL issue (40m/16873).
ULSEN is sensing the optic motion but ULCOIL cannot move the optic.
We confirmed that the coil input is there upto satellite amplifier output.
We also checked that ULCOIL have 3.3 mH and 16 Ohms, which are consistent with other coils.
We need to investigate ITMY ULCOIL in the next vent.
What we did:
- Checked again that C1:SUS-ITMY_ULCOIL_OFFSET does not kick ITMY using OSEM sensor signals and oplev signals. ULSEN moves when ITMY is kicked by other coils.
- Checked that kick gives voltage changes at coil driver and satellite amplifier output. We unplugged J1 DB25 cable from the feedthru flange and checked the signals sent to coil with oscilloscope.
- Measured inductance (using BK PRECISION LCR meter) and resistance (using Fluke) of coils for ITMY. Below is the result. UL coil seems to be consistent with other coils. (It seems like BK PRECISION one wil give wrong resistance if the dial is set to the resistance value which is too low compared with the one you want to measure. If you want to measure 16
Ω, set the dial to larger than 20
Ω, not 2
Feedthru connector: ITMY1
Pin 3-15 / R = 16.3Ω / L = 3.32 mH (UL)
Pin 7-19 / R = 16.4Ω / L = 3.30 mH (UR)
Pin11-23 / R = 16.2Ω / L = 3.31 mH (LL)
Feedthru connector: ITMY2
Pin 3-15 / N/A
Pin 7-19 / R = 16.3Ω / L = 3.30 mH (SD)
Pin11-23 / R = 16.4Ω / L = 3.33 mH (LR)
- UL is the only short OSEM in ITMY OSEMs.
- ITMY have dumbells for magnets.
- If UL magnet is off, ULSEN would not work. Something not magnetic is working for shadow sensing for UL? Dumbells?
- ULSEN just sensing some coupling from other OSEMs?