Reports until 14:52, Friday 19 October 2012
H1 SUS
mark.barton@LIGO.ORG - posted 14:52, Friday 19 October 2012 (4491)
Watchdog DC path filters fixed on MC1, MC2, MC3, PRM, PR2, PR3 and SR2
Mark B.

Jeff K and I both noticed that the watchdog DC band-limited signals on MC2 and PR2 were suspiciously small and that in fact the wrong filter, with no response at DC, had been installed. I traced this to a bug in ^/trunk/Common/MatlabTools/make_OSEM_filter_model.m, ultimately called by .../prepare.m. The section of code from line 235 had "ac" in several places where it should have had "dc" and so was loading the AC filter instead. I fixed the error and committed the new version.

I tested the fix by re-running prepare.m on MC2 and it did install the intended filter (flat up to 10 Hz and then rolling off). 

Because the code is used by all HAM triples, I then reran prepare.m on all the others in H1, i.e., MC1, MC3, PRM, PR2, PR3 and SR2. After running prepare.m for each suspension, I clicked LOAD COEFFICIENTS on all 6+4+4 filters in the DC path blocks of the three levels of watchdogs for all suspensions, and re-enabled damping for installed suspensions.

There are currently no other types of SUS-scope suspensions on H1 but for good measure I checked FMy and ETMy on H2 and they had the right filter already.

The same fix will need to be applied to the HAM triples at LLO.