Difference between revisions of "Minutes-4-29-2010"
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- PCBs: some minor modifications have been done and the design is now final. Kim got quotes from San Francisco Circuits ($76K) and CEM ($41K) for 28 of each board. Both are bellow our budget ($98K). CEM has special notes: quotation based on using FR4 instead of G10 material (not acceptable!) and that the flatness specs may not be achievable. Bill, Brian and Fernando discussed what is our actual flatness requirement. Kim expects one more quotation. | - PCBs: some minor modifications have been done and the design is now final. Kim got quotes from San Francisco Circuits ($76K) and CEM ($41K) for 28 of each board. Both are bellow our budget ($98K). CEM has special notes: quotation based on using FR4 instead of G10 material (not acceptable!) and that the flatness specs may not be achievable. Bill, Brian and Fernando discussed what is our actual flatness requirement. Kim expects one more quotation. | ||
| + | - The "power outage test" last Friday showed that the source of the oscillations is not external. After all the power was shut down at 6pm, the oscillations remained exactly the same as before. Same test was repeated on Monday early in the morning when the scope showed only few mV (on 10MOhm probe) random noise, and the result was the same. We moved the chamber back in the tent for testing. Lubomir did some investigations: the old cathode board had no oscillations when the cable was grounded properly. All of the new cathode boards showed oscillations that were reduced significantly in amplitude when grounding the cable from the chamber side. The oscillations are stronger at one side of the card; the speculation is that the line used for calibration that goes to the input of the preamplifier that is at the same side may be responsible for the feedback. If nothing else works, Lubomir suggested to reduce the amplification of the new cathode cards so that they can be used for the prototype tests. | ||
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== Cathode redesign == | == Cathode redesign == | ||
Revision as of 16:36, 29 April 2010
April 29, 2010 FDC meeting
Tentative Agenda
- Production space
- status
- off-site space production planning
- Electronics
- PCB (Kim, Fernando)
- grounding/oscillation tests (Lubomir)
- Cathode redesign (Roger) beam hole, fdc left, cathode adapter
- Cosmic tests (Beni)
- results from the first tests FDC Log Book
- plans
- Other
- talks at the Collaboration meeting
- open house
Minutes
Participants: Fernando, Casey, Roger, Brian, Glenn, Bill, Kim, Simon, Beni, Eugene, Lubomir
Production space
- Tim is the contact person from our side for the 727 B.C. property. He will meet with Rusty to discuss our requirements and all the details. There was a meeting with the network people from the computer center. They will organize the network using their equipment. We will pay for the COX business connection.
- A document has been created (attached above) with the intention to list all the steps of the FDC production and describe them in terms of manpower and time. Lubomir will seek help from Brian and Mark to estimate the manpower required for each step. The wire stringing procedure will be based on the UVA experience. Then Bill will review the document and we will continue with creating a flowchart of the production.
Electronics
- PCBs: some minor modifications have been done and the design is now final. Kim got quotes from San Francisco Circuits ($76K) and CEM ($41K) for 28 of each board. Both are bellow our budget ($98K). CEM has special notes: quotation based on using FR4 instead of G10 material (not acceptable!) and that the flatness specs may not be achievable. Bill, Brian and Fernando discussed what is our actual flatness requirement. Kim expects one more quotation.
- The "power outage test" last Friday showed that the source of the oscillations is not external. After all the power was shut down at 6pm, the oscillations remained exactly the same as before. Same test was repeated on Monday early in the morning when the scope showed only few mV (on 10MOhm probe) random noise, and the result was the same. We moved the chamber back in the tent for testing. Lubomir did some investigations: the old cathode board had no oscillations when the cable was grounded properly. All of the new cathode boards showed oscillations that were reduced significantly in amplitude when grounding the cable from the chamber side. The oscillations are stronger at one side of the card; the speculation is that the line used for calibration that goes to the input of the preamplifier that is at the same side may be responsible for the feedback. If nothing else works, Lubomir suggested to reduce the amplification of the new cathode cards so that they can be used for the prototype tests.
Cathode redesign
- Roger discussed the plots attached above. Everybody agreed on the design of the beam hole (first plot). had several questions related to the ground of the cathode daughter board (flex) design, and also the strip labels.
