Minutes of feedthrough meeting of 13 May, 2002.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Present: Pof, FH, PB, WW, ML, AD, ASD

*) Milestones:

	- ft39 has been rebuilt and welded after disassembling
	  to remove the leaky cold flange.  One of the 
	  pincarrier / cold flange welds on the original
	  ft39 had been found to leak on the original ft39.
	  That leak had not been detected during the leak check
	  of the flange alone.  We will therefore start a
	  general practice of leak checking all flanges twice
	  (by two different people) before using the flange
	  in a feedthrough.  The weld on the original ft39
	  cold flange will be repaired, and the flange will
	  be remachined by Dave Smith and then tested so that 
	  it can be kept as a spare.  The funnel of the
	  original ft39 is not reusable.

	- ft40 final electrical tests were completed

	- ft41 was cold tested.  There was an "opposite channel"
	  short between channels 23 and 24 of slot six when the
	  feedthrough was cold, so ft41 will be reopened and both 
	  vacuum cables of slot six will be replaced.  We neglected 
	  to check when the feedthrough was cold which vacuum cable
	  was defective, so both vacuum cables will be placed in
	  the "rejects" box and noted that one or the other is
	  defective.

	- ft42 has been built and welded.  One pin in the warm flange
	  was badly bent during vacuum cable installation, to that
	  flange was removed and replaced with another.

	- Two more flanges were welded.  The original warm flange of
	  ft42 also had the pincarrier with the bent pin replaced.

*) The order with BAY Associates for 250 feet of solid 24 AWG wire 
   insulated with Kapton for attaching the RJ11's to the RTD wires
   has fallen through; they were apparently out of kapton and
   did not want to carry on with the order unless we increased the
   order to 5000 ft!  Another vender (Arcor Electronics) has been
   found, who will supply 1000 ft of the same wire for US$221.50
   with a three to four week delivery time.  Meanwhile, Roy has
   also purchased at CERN 100 meters of stranded 24 AWG wire insulated
   with Kapton, and that wire is presently in transit to Victoria.
   The stranded wire (or perhaps just its Kapton insulation) can be 
   used as a fall back in case the other order does not come through.

*) It was found during installation into one of the feedthroughs that
   the centre part of the ATI (the part that houses the 64 sockets) 
   on pigtail 6208 protrudes about 3 mm beyond normal.  Conseequently,
   the jackscrews just barely bight the pinarrier threaded holes,
   and the base of the ATI bottoms out on the base of the pincarrier,
   possibly causing shorts to ground.  These problems could be
   overcome by some minor machining of the jackscrew posts, and
   using some nylon washers to prevent the ATI from bottoming out.
   A full 64x64 cross talk check has done for pt6208 (a T48) and
   no problems found.  We will therefore not return pt6208 to
   Axon but keep it as a spare (we have 12 spare T48's, of which
   two have already been damaged).  Note that Laurent Serin has
   informed me that "The interaction with Axon, now we are very near 
   the end of the market, is more and more difficult".

*) With the help of Neil, we will devise a method for quick 
   continuity and ground-short checks to be made when the
   warm cables are plugged into the ambient flange pincarriers.
   A connector mounted onto a small pc board will be plugged into
   the warm cable being installed, and similarly a micro-D socket 
   mounted on a pc board will be plugged into the corresponding
   pigtail cable.  The pc boards will be made with shorts between
   neighboring channels such that there will be continuity between
   channel 1 and channel 64 if and only if all pins are mated
   correctly in the correct sockets.  There will be a battery
   powered green led on one of the connectors to indicate that
   the continuity check is successful.  There will also be a ground
   connection on the test connector, with a red led to light up
   if there is continuity between any pin and ground.

*) As of 17 May, Aboud still feels that the first week of July is
   the best estimate for the commencement of feedthrough installation.
   Aboud also writes "During the last  week of June, I would like to 
   check necessary tooling, bolts, O'rings, RF gaskets, pigtails & 
   connectors protection, f-t labeling on the cryostat etc. 
   Paul Birney help will be very useful for us during this period.

*) Pof phoned Kelly at Dove travel to check on flight availability
   for late June and early July.  Here are a few key points:

	-) Tickets may be booked but not paid for up to one week.

	-) Three weeks is still the break point for "cheap" tickets,
	   BUT the flights are starting to fill up, especially the
	   routes within Europe.  Kelly recommends booking next week. 

	-) Even with the cheap tickets, the return date may be
	   changed for a "change fee" of $145.00.

Agenda for next week (Tuesday 21 May)
^^^^^^^^^^^^^^^^^^^^
- Milestones
- June/July/August CERN travel plans
- Plans for the week
- AOB