07/03/16

The new snout doesn't fit due to the screw holes being misaligned. I am going to try modifying the old one (that was in conflict with some material in the base) over the next couple of days. It is too long by 11mm, so if I can remove that it should then fit..

So after some modifications to the supports, the PSUs and NIM crates are now fully isolated from the frame.

I am currently working through changing all the guide pins for the new plastic ones and adding the shielding gasket.

Shunji made an interesting comment when we were discussing isolating the FEEs yesterday, in that, the ground connections for the chiller and the power we provide to our PSUs are connected to the same network.

    - I measure the resistance between the chiller ground and the power ground to be 2.5 Ohms.

    - The resistance between the chiller ground and the main Cu water pipe is ~2.2 kOhms.

    - We have three possible options here (that we have come up with so far):

          * disconnect the chiller ground from the network -> potentially very dangerous

          * put  a large resistance in between the chiller and the ground

          * Shunji has available a noise cut trans with up to 30A capability that could be used for our NIM crates and power supplies (I think we draw < 30A IIRC)  [photos attached]

I will carry out some short pulser tests with a DSSSD connected via the most recent kaptons this afternoon to see what effect the isolation and gasket has had so far.