Difference between revisions of "Minutes-6-3-2010"

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= Minutes =
 
= Minutes =
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Participants: Bill, Eugene, Mark, Brian, Casey, Beni, Simon, Lubomir, Gerard (on the phone), and  Glenn and Fernando (at the end)0
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Participants: Eugene, Bill, Fernando, Glenn, Casey, Mark, Beni, Simon, and Lubomir
  
 
== Production ==         
 
== Production ==         
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- Bill informed us that Ron Bartek promised Tim the specifications for the off-site space to be  delivered to Rusty
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Sprouse no later than Friday. There's no full lease of the property yet. Eugene explained us there's a relation between setting up the Blue Crab off-site space and the Hall B one: same people are involved. 
  
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- Bill informed us that Ron Bartek had finished the design and the specifications for the infrastructure of the off-site space were given to the procurement. The information is that a DOE approval might be required. Eugene will contact Teresa Danforth to speed up the process.
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- Bill will take care about creating the production flowchart with Fast Track, based on the above document.
  
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- Bill will take care about creating the production flowchart based on the above document.
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- Brian will bring the fixtures for the wire stringing from UVA on Monday (06/07) and put them in 126. Mark will find space to store the equipment in F117 and as long as there's more free space there, Bill is ready to start setting up the wire stringing. We will use the first articles of the PCBs and cathode foils to produce the new design prototype. We discussed whether we can do the same with the wire and cathode frames: submit PRs for all the frames and use the first ones for the prototype. Bill is confident that the new design will work and we can submit PRs for all the frames; Eugene and Lubomir are also in favor of such decision but we will re-visit this on the next meeting.  
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- We discussed a plan to build a one-layer prototype based on the new designs of the frames, PCBs, and cathodes, and also using the UVA equipment for wire stringing. We will use the first article PCBs and cathodes to make the prototype. Brian will help with the transportation of the wire equipment from UVA; Lubomir will contact Nilanga in this respect, as well. The idea is to set up first the wire stringing at room 117.
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== Electronics ==
 
== Electronics ==
  
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Lubomir showed two pictures linked above: with the raw fADC data, showing strong oscillations (coming from the CAEN HV) and after subtracting the oscillations using the unaffected channels (second picture left panel). Right panel shows the ratio of the strip to wire signal as it changes with time. We discussed what is the origin of the delay: top strips coming before, and bottom after the wire signals by about 8ns. By swapping cables, cards, fADC connector we should be able to identify this. The noise is reduced significantly after the correction. This allows to obtain very high resolution from the cathodes. Page 465 of the FDC logbook shows the wire position reconstructed from the cathodes minus the actual wire position. 5 strips were used on each side and the wire position resolution is about 400microns, which corresponds to about 70microns position resolution of the cathode coordinate. If three strips are used (page 464), the resolution is a factor of two worse. Gerard (on the phone) asked what is the algorithm for the strip coordinate reconstruction, and what information is needed from each channel. The best resolution is obtained by integrating the charge from each strip  for the time of the first peak as defined by the wire. This probably will not be possible to implement in the FPGAs, but Gerard will work on that and also on extracting the timing information from the fADC. First of all, Gerard will work on the fADC so that the firmware is loaded from the permanent memory when the module is powered up. Now we need to load it from a laptop.      
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- Fernando informed us that the DAQ group (Bryan Moffit) is working on the drivers for the fADC125 with LINUX CPU. Beni said he would prefer to use the CPU we have now (VXWorks) because if we can have the LINUX one it will be temporary. Eugene suggested buying a LINUX CPU. Beni explained the three CPUs available now are from different companies, the DAQ people are evaluating them and we better wait before buying such a CPU. Fernando will ask Bryan when we may expect the drivers for the VXWorks CPU. By that time we will use the fADC with the Gerard's program.  
  
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- the PR for the PCBs were submitted, expect to have the first article in August.
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- Fernando investigate the noise coming from the CAEN HV supply. It radiates rather than transmits through the cables. The strips and wires (mainly the long strips) are picking up that noise. Fernando reduced the noise by re-ranging the ground cable connections. Still two of the cards are showing 
  
 
== Cathode redesign ==
 
== Cathode redesign ==
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Roger is working on the Bill's modifications, hopefully will have them done soon.
 
Roger is working on the Bill's modifications, hopefully will have them done soon.

Revision as of 16:33, 3 June 2010

June 3, 2010 FDC meeting

Tentative Agenda

  1. Production
    • 727 B.C. status
    • production planning
    • new design one-layer prototype: PCB and cathode PRs, wire stringing fixtures
  2. Electronics
    • fADC125 status (Fernando)
    • PCB status (Kim, Fernando)
    • CAEN HV noise investigations (Fernando)
  3. Cathode redesign Bill's changes proposed on the last meeting (Bill, Roger)
  4. Full-scale prototype test results
  5. Other


Minutes

Participants: Eugene, Bill, Fernando, Glenn, Casey, Mark, Beni, Simon, and Lubomir

Production

- Bill informed us that Ron Bartek promised Tim the specifications for the off-site space to be delivered to Rusty Sprouse no later than Friday. There's no full lease of the property yet. Eugene explained us there's a relation between setting up the Blue Crab off-site space and the Hall B one: same people are involved.

- Bill will take care about creating the production flowchart with Fast Track, based on the above document.

- Brian will bring the fixtures for the wire stringing from UVA on Monday (06/07) and put them in 126. Mark will find space to store the equipment in F117 and as long as there's more free space there, Bill is ready to start setting up the wire stringing. We will use the first articles of the PCBs and cathode foils to produce the new design prototype. We discussed whether we can do the same with the wire and cathode frames: submit PRs for all the frames and use the first ones for the prototype. Bill is confident that the new design will work and we can submit PRs for all the frames; Eugene and Lubomir are also in favor of such decision but we will re-visit this on the next meeting.

Electronics

- Fernando informed us that the DAQ group (Bryan Moffit) is working on the drivers for the fADC125 with LINUX CPU. Beni said he would prefer to use the CPU we have now (VXWorks) because if we can have the LINUX one it will be temporary. Eugene suggested buying a LINUX CPU. Beni explained the three CPUs available now are from different companies, the DAQ people are evaluating them and we better wait before buying such a CPU. Fernando will ask Bryan when we may expect the drivers for the VXWorks CPU. By that time we will use the fADC with the Gerard's program.

- the PR for the PCBs were submitted, expect to have the first article in August.

- Fernando investigate the noise coming from the CAEN HV supply. It radiates rather than transmits through the cables. The strips and wires (mainly the long strips) are picking up that noise. Fernando reduced the noise by re-ranging the ground cable connections. Still two of the cards are showing

Cathode redesign

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