F. Clara, J. Kissel. T. Sadecki

We reconnected and reinstalled the BOSEMs to the TOP stages of what-is-now H1 SUS ITMY (but is still being run on H2 SUS ITMY electronics), gathered and installed new open light current values (as the resistance of the long temporary cables significantly reduced the voltage at the ADC, see table below), and aligned them by-eye laterally, and by and axially by speed dials.

After resurrecting the sensor diagonalization templates 
${SusSVN}/sus/trunk/QUAD/H2/ITMY/SAGM0/Data/
20110803_ITMY_Diagonalize_1p3_Yaw.xml
20110803_ITMY_Diagonalize_2p2_Vert.xml
and finding that the isolation between expected and unexpected degrees of freedom was not-so-hot, we took a few averages of M0 P to P and V to V TFs using
${SusSVN}/sus/trunk/QUAD/H2/ITMY/SAGM0/Data/
2012-02-15_1802_H2SUSITMY_M0_Mono_V_WhiteNoise.xml
2012-02-01_H2SUSITMY_M0_Mono_P_WhiteNoise.xml
(which are sorely out of date) and found both to be crap (really noisy, low amplitude, little-to-no visible resonances). After a few tweaks here and there, we found that the bump stops on the reaction chain were rubbing against the main chain. What's worse, is that we saw the top bump stop rubbing first ("sweet! we'll just tweak up the pitch"), but then noticed the -Y bump stop was also rubbing ("that requires adjusting yaw, that's hard, let's go home instead").

So, indeed, we will leave further alleviation of rubbing for Monday.

Welcome back to QUADs everybody!


%%%%%%%%%%%%%%%%% Open Light Current Values %%%%%%%%%%%%%%%%%
BOSEM      Production      Test Stand     % Drop
Name       OLC [cts]       OLC [cts]      [%]
M0 F1      30805           29529          4.14
M0 F2      30164           28758          4.66
M0 F3      30160           28942          4.04
M0 LF      28050           26914          4.05
M0 RT      26205           25128          4.11
M0 SD      31046           29590          4.69

R0 F1      25530           24943          2.3
R0 F2      26272           25238          3.93
R0 F3      27538           26342          4.34
R0 LF      29513           27787          5.85
R0 RT      25210           24760          1.79
R0 SD      27113           26124          3.65


(Note, I gathered the previous OLC values from what was installed in the offset/gain fields; I couldn't find a report of them in the log [though I didn't try that hard]. For M0, I gathered to offsets and gains before I started entering in the new values, hence I trust their accuracy. For R0, I entered in the new offsets before remembering to get the old values, so I had to use the gains [which are entered in with less precision], so that's probably why the % drop varies by ~1% from 4%.)

-- Huh! A ~4% drop. Since V=IR, and nothing else has changed, I guess we know that there's therefore a 4% increase in resistance between the production sensor readout chain and the test stand. No show stopper, just good to know, and annoying to have to redo the normalization.