Minutes of the SCT links meeting of 20 June 1997.

John Dowell reported that further PIN diode irradiation studies 
would take place in ISIS starting in June and at the PS starting
August 25th, with fluences in each case of approximately 2*10^14/cm^2. 

Dave White has now measured 12 DORIC and 12 LDC chips and found that
all work.  Tests of the full functionality of DORIC are awaiting
completion of a test board for generating bi-phase mark signals.
Four chips of each type will be irradiated at ISIS starting in June.

The GEC-Marconi packaging effort with Sandia VCSELs is in progress.
GEC claim to be able to package the devices over the summer providing
they are supplied soon by Sandia.  The VCSELs will be supplied as
single devices (cut from their array by Sandia).  In discussions it
was decided to consult the group from the LAr calorimeter working with
VCSELs and try to use their experience in producing VCSEL packages with
GEC.  Tony Weidberg will follow this up.

The work plan for the coming months was then discussed.  Bob Kowalewski
proposed having a working, bi-directional prototype link set up to allow
evaluation of individual link components.  This was agreed to be worth
doing, and one would ideally have one such prototype in the UK and one
in Switzerland.  In an initial phase one would use dummy modules which
could, e.g., merely feed the clock and control data into the LED drivers.

It was decided to order approximately 16 packages from GEC (with LEDS and
the new epitaxial PIN diodes) for use in these prototypes and in TSP
links for 1998.  Expected delivery time is approximately 4 months.  A
larger quantity (~100) of unpackaged epitaxial PIN diodes will also be
ordered for irradiation and lifetime studies.  

The following list of tasks was shown and discussed.  Where there was
agreement on the sharing of responsibilities the responsible group is
indicated.  A question mark after the group indicates that while the
group is in principle interested in working on the item it is not yet
in the position to commit itself there.

   Optoelectronics:
   ===============
    /    * Obtain GEC packages with LEDs, new PINs
UK <     * Explore VCSEL packaging
    \    * Radiation tests of DORIC, LDC; follow up

   Fibers:
   ======
     /   * Protection in INDET volume
Birm/    * Connectors
    \    * Patch panels
     \   * Protection outside ATLAS

   Off-detector receiver:
   =====================
(CERN?)  * Integrate preamp and discriminator
Geneva?/ * Design and implement calibration circuit for receiver
       \ * Multichannel design (density, noise performance)

   TTC encoding, sending:
   =====================
Oxford   * Complete the board for encoding protocol, driving LEDs
Geneva?/ * Explore use of commercial VCSELs
       \ * Multichannel design

   Optical hybrids:
   ===============
Geneva   * Produce PCB for near-term tests
Geneva?  * Produce ceramic board for ATLAS use

   Link test facility:
   ==================
         * set up full working link (both directions)

   TSP for 1998:
   ============
         * produce a number of links to be determined