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Reports until 14:46, Tuesday 01 March 2016
H1 SEI
jim.warner@LIGO.ORG - posted 14:46, Tuesday 01 March 2016 (25809)
Slight change to HAM5 isolation filters

Nairwita and Jeff found yesterday that the foton file for HAM5 did not show the same controller that the seismic matlab commissioning scripts said were installed. The changes weren't huge (some very different low frequency gains, but only factors of a couple at a few hz), and are shown in the two attached plots. First figure is the old filters, second is the new filters. While everything was down this afternoon I've installed the Matlab filters. I don't expect any difference in the performance at HAM5, the diffrences are not huge, this was mostly a housekeeping task, to make offline modeling work easier. I still haven't figured out why the difference, but it would likely take digging through months of archived foton files. This also makes the controllers at HAM5 more similar to HAMs 4&6 over 1-10hz.

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