H1 SUS OFI Signal Chain Functional, Damping Loops Work, AOSEM Noise Is Good

J. Kissel, M. Pirello, R. McCarthy

Continuing along with the new HAM5/6 electronics adventure, we were able to make the H1 SUS OFI signal chain completely functional today. The electronics are final and as designed. As such, I was able to confirm that 
   (a) The suspension remains free after pump-down (yes!)
   (b) The damping loop design from yesterday works well (yay!)
   (c) The AOSEM noise floor is below spec / requirements (yeah!)

Attached are screenshots of the (newly taken) undamped transfer functions, (newly taken) damped transfer functions, and (newly taken) amplitude spectral densities.

%% Details %%
Undamped Data Files:
/ligo/svncommon/SusSVN/sus/trunk/OFIS/H1/OFI/SAGM1/Data/
    2018-01-19_2151_H1SUSOFI_M1_WhiteNoise_L_0p01to50Hz.xml
    2018-01-19_2151_H1SUSOFI_M1_WhiteNoise_T_0p01to50Hz.xml
    2018-01-19_2151_H1SUSOFI_M1_WhiteNoise_Y_0p01to50Hz.xml

Damped Data Files:
/ligo/svncommon/SusSVN/sus/trunk/OFIS/H1/OFI/SAGM1/Data/
    2018-01-19_2312_H1SUSOFI_M1_WhiteNoise_L_0p01to50Hz.xml
    2018-01-19_2312_H1SUSOFI_M1_WhiteNoise_T_0p01to50Hz.xml
    2018-01-19_2312_H1SUSOFI_M1_WhiteNoise_Y_0p01to50Hz.xml

How we made it work:
(1) The OFI's coil driver is *not* an ISC configuration HAM-A driver chassis (No chassis drawing exists, only front and back panel drawings; see complaints about that in LHO aLOG 8772), it's a regular ol' HAM-A driver (D1100687)-- but both use the HAM-A board D1100117. That means we'd forgotten to jumper the "Test/Coil Enable" switch. That means out OFI's DAC drive wasn't making it into the coil driver circuit. Richard realized this and had Marc pull the chassis and jumper the appropriate pins on the board. While at it, we made the executive decision to jumper the Lowpass Filter ON as well, such that it behaves identically to an ISC configured HAM-A driver.
(2) The drawing for cable arrangement on the vacuum flanges of HAM5 (D1002876-v4) is not up-to-date. As such, I discovered (after driving ZM2 with the OFI signal chain!!) that ZM2 and OFI cables were swapped at the vacuum flange, because whomever installed them couldn't possibly have known. We now have the cables correct, and 
   - ZM2 (on cable SUS-SQ-21) is plugged into 
      - Conflat D3 (the furthest +X, on the beam splitter side of HAM5), 
      - Flange 2 (lower left, if you're looking at the chamber from the air side with the beam splitter to your back)
      - Connector 2 (the bottom DB25)
   - OFI (on cable SUS-SQ-30) is plugged into
      - Conflat D3 
      - Flange 3 (lower right, if you're looking at the chamber from the air side with the beam splitter to your back)
(3) I had not yet installed the proper COILOUTF driver electronics frequency response compensation (primarily because there's an innocuous bug in the coil driver state machine code, 'cause it was built for a 4 OSEM system, and we're using it here on a 3 OSEM system).
Having fixed those three problems -- we're good to go!