Minutes of FPS detector meeting, 9/14/99 at BNL, Rm. 2-160, 9-10:30 am
In attendance: S. Desai (scribe), M. Rijssenbeek, A. Talalaevskii, J.
Steffens, J. Brody, A. Patwa (co-scribe), P. Yamin
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Main Agenda: Status report on FPS LED calibration system 
			(A. Talalaevskii, M. Rijssenbeek)
	     Discussion (all)

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o M. Rijssenbeek gave a status report on the production of calibration
  systems and individual parts required for the system (i.e. connectors,
  resistiors, boards, fibers, etc...) The bottleneck at this stage is
  getting fibers.

  Further, for reference, the following table describes the total
  soldering and assembly we have at the moment (adapted from MR's
  table, as of Sept. 14, 1999):

        Item                                    Assembled
        1. solder Resistors                        40
        2. solder LEDs                             30
        3. solder connector                        45
        4. assembled support                       90
        5. Total Assembly                          15
        6. fiber stop (glue beads)                 34
        7. fiber insertion                          0
        8. packaging                                0

  Fiber insertion hasn't begun since 24" fibers are not fully delivered
  from fermilab but we've suggested to begin assembling with the 34 long
  (24") and 840 short (21") fibers that we currently have on hand in SB.
  The remaining, final batch of long fibers can then be inserted upon 
  arrival from fermilab and "continue" production from there.

o A. Talalaevskii showed us the reference system box which he has
  constructed. It still needs a little more work but is largely completed.

o A. Talalaevskii also presented preliminary measurements of the 1 MIP
  signal. However, they did not exhibit the appropriate behavior as the
  discriminator threshold used to generate the gate was varied.
  S. Desai spoke with A. Talalaevskii last night (Sept. 14), at which time
  he appeared to have overcome the problem by amplifying the PMT output
  *before* splitting the signal into data and trigger signals.

o J. Steffens has completed another 8x8 Matrix for the MAPMT.  While
  A. Talalaevskii is completing the MIP meausrements and finishing up the
  reference box, S. Desai will be using this to choose channels for use
  during installation and tuning of the calibration systems.

o J. Steffens & co. are presently working on a fixture/jig to put 
  beads/stoppers on clear fiber ends that get inserted to cylinders.  this
  will be some fixture with 9-channels that provides better glue 
  uniformity around individual clear fibers and allows more to be
  assembled with stoppers than previously.

o The system configuration for calibration system tuning will be
  [Module+Cal Sys]c1[Clear Fibers]c2[Dark Box w/ MAPMT], w/ c1
  and c2 as connectors.  Once we have the Clear Fibers and Dark
  Box, channel to channel gain calibration (downstream of c1) will
  be done using Andrei's reference system,as it will be tuned to
  produce uniform output.

o We still need to settle the issue of the design and construction of
  The Dark Box (we could conceivably use the one already in the
  clean room, in which case we need to decide how it should be
  modified).  That is, the large box we have may require some modification
  for use such as a hole for fiber pigtail adapter, electrical connection
  plates, etc... but at the same time, are also looking into
  making/finding a smaller box that can accomodate MAPMT and other
  electrical connections/fibers associated with the MAPMT.  The smaller
  box is more convenient and would like to consider making one (provided
  nothing is easily found at BNL) perhaps, next week.

o Tuning of the calibration systems will be done at BNL, probably at
  night to prevent interference with work done during the day.  This
  also has the advantage of decoupling the tuning process with the
  installation process which may be done during the day.

o Finally, delivery of "initial" calibration system boards to begin
  installing in final modules (LMs) is contingent somewhat on delivery
  of long fibers but has been projected to be end of next week/early
  following. The 24" fibers are being completed this week at FNAL and are
  expected to also arrive sometime next week.