Gerardo, JeffB, Mike, Hugh, Travis, Appollo, Kiwamu,
We have removed two irises from the output faraday isolator (OFI). They were originally meant for a temporary tool for aligning the OFI and we simply forgot to remove them. So we opened up the HAM5 north door and locked the north side of the ISI. Then we took out the two irises -- one at the input side and the other at the output side. Note that we left the irises' holders attached. Also, Gerardo replaced the holder at the output side with a clean one because the one we had was not class-A compatible.
After unlocking the ISI, Hugh checked the balance of the ISI and he did not see a significant change. So we did not have to put a counter weight as expected.
We revisited the HMA5 installation exit check list, performed those activities and found nothing special. So it is good.
Some pictures will be uploaded later.
Here is 12 hours of the Vertical CPS channels. The left three are the local in counts and the right three are Cartesian in n(m/rad) Nice that we can so clearly see a 22 gram payload change. In the local basis we have +-1600 lock unlock shift spec as being balanced close enough. When I balanced this on 21 July , the shifts were <200cts. So the comparison seen before and after the disturbance when JeffB half locked the ISI and ISC removed the irises are still well within our spec. The signs and magnitudes all make sense (Thanks ISC for this check!) with the worst being RX tilting 6urads.
Link to ResourceSpace.