Minutes-3-4-2010

FDC Weekly Meeting

Date: March 4, 2010

Participants: Daniel, Simon, Beni, Lubomir, Bill, Roger, Fernando, Eugene, Brian, Glenn, Chuck, Kim

Next Meeting: March 11, 2010

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Construction Space

 - Lubomir has prepared a floor plan layout that was sent to Glenn for action 
   and planning. Glenn has gone over this with Rolf Ent and they are working 
   out a plan. Stay tuned.
 - Lubomir will be in charge of working on a plan for appropriate clean
   space for FDC construction in EEL 126.
 - Lubomir will work with Bill to procure our second granite table.

General Construction Updates

 - The two-layer prototype continues under source tests in the cosmic ray
   test facility. We plan to open up the detector for work on and inspection
   of the HV busses by March 15 to give DSC time to work on the detector 
   and also to diagnose the problem before circuit board procurement.
 - The third wire/cathode layer is ready for testing pending availability
   of manpower.
 - We want to try putting the oxygen sensor in our system and measure the
   oxygen contamination on our input and output lines. Due to the worries
   about high input impedance of this device, we have some additional
   checking to do. We will test pending availability of manpower.
 - The preliminary FDC stack assembly document draft is located at:
   /u/group/halld/Engineering/PRELIMINARY DOCUMENTS. We will review this
   document in the coming weeks to update out-of-date or old procedures.
 - Fernando would like us to add the final version of the HV multi-pin
   connectors to the full-scale prototype. We will do this when the 
   detector is taken apart.
 - Fernando needs us to finalize the wire and cathode naming conventions
   for the FDC. Lubomir will take responsibility for this work.

Frame Modification Studies

 - The dummy Kapton cathode has been laminated to its frame. The Mylar
   version did not adhere well and had to be scrapped. The plan is to use
   the cathode material to simulate the second cathode plane and the ground
   plane. Work on this will continue next week pending availability of
   manpower.
 - Bill has put together a few slides showing the frame design changes.
 - The redesigned frame piece for the wire board is expected back from
   the shop within a couple of weeks.

Wire Frame Update

 - The wire frame construction document is located at:
   /u/group/halld/Engineering/PRELIMINARY DOCUMENTS.
 - Kim has circulated the PCB drawings to the group for feedback and review.
   We should have about 3 weeks to complete this work. The plan is not to
   move forward with procurement until after inspection/diagnosis/repairs
   of the HV/current problems seen in the full-scale prototype.
 - The single piece PCB version and the version reducing the PCBs from
   six to four pieces has been set aside due to excessive costs.
 - DSC is finalizing the tension specifications for winding. It looks like
   the +/-5% spec is unnecessarily tight. Looks like +/-20% is full
   satisfactory.

Cathode Update

 - The current draft of the cathode construction document is located at:
   /u/group/halld/Engineering/PRELIMINARY DOCUMENTS.
 - The cathode board stock material has been delivered to Allflex for
   storage.
 - The next rigid-flex design meeting will take place shortly.
 - We would like to push to get the cathode board procurement done by the
   end of March.
 - David Lawrence is working to give us input on the hole size in the
   cathode center. Stay tuned.

Prototype Testing

 - The current version of the full-scale prototype test plan is on the
   GlueX portal as (GlueX-doc-1304).
 - To connect the full-scale prototype to the readout electronics, Fernando
   is designing a simple translator board that allows connection from the
   24-channel preamp connector to the 16-channel connectors on the ADCs and
   TDCs. These boards should be ready next week. 
 - The signal cables for the full-scale prototype are being made up by
   Fernando's group and will be ready shortly.
 - Two layer test update: See plots made by Beni and Lubomir in the
   FDC Log Book.
 - The delivery of the remainder of the preamp cards for the full-scale
   prototype will be in mid-March.
 - Fernando will pursue purchasing enough cathode ground boards for all
   six cathode planes for the full-scale prototype.
 - A while ago we focussed on the wiggles seen in the reconstructed wire 
   position from the cathodes (see log entry 419) in the
   FDC logbook. We believe that the periodicity seen is due to the algorithm
   Beni is using to determine the U and V centroids. Stay tuned.
   

Construction Updates

 - The sense wire SEM checks are now complete and the wire sample reports
   have been posted on the FDC Reports Page. 
 - DSC talked to Keith Solberg at IUCF this week regarding the status of the
   review of the Phase 3 budget for the wire winding. Keith will be meeting
   with Vladimir Derenchuk early next week for final review. They indicated
   that we should have the budget in the first part of next week.
 - It is time for the next Phase 3 preparation meeting with Keith Solberg,
   Bill, and DSC. DSC will work to schedule this only after we have a
   preliminary Phase 3 budget in our hands. See the work plan at: 
   Phase 3 Preparation Work
 - Master list on wire and cathode frame redesign work is located at:
   Frame Modification Work.
 - Bill has circulated a brief write-up regarding the plans for the summer
   work at IUCF. We are reviewing it internally. We will schedule a meeting
   with Keith and Vladimir shortly after we have discussed it so that they
   can prepare a budget estimate for the work.

Work List

 - The FDC short-term work list has been posted on the FDC web site.  
   This is continually being updated and DSC welcomes any feedback or 
   comments from the group.

Minutes prepared by Daniel. Send any comments or corrections along.