Minutes of feedthrough meeting of 17 April, 2000.
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Present: GV, Pof, MLenc, RL, JL, TH, PB

*) Milestones:

	- Terry received the ferrite scope for measuring
	  the ferrite content of welds.  Its quick and
	  easy to use, accurate to about 10%.

	- Cold thermal tests were done with the bellows
	  pressure at 1.0 and 1.5 atmosphere.  The prototype
	  flange heater was installed for these tests.
	  Terry will crunch the numbers and report next
	  week.  The thermal tests will be repeated one more 
	  time at a higher temperature (the flange temperature
	  reached a maximum of 33 degrees; we should take it to
	  50 degrees) and with the `production' thermal interface
	  (replacement for thermal grease, not yet ordered)
	  between the resistors and heater plate, and between
	  the heater plate and the warm flange.

	- Electrical tests were repeated at the cold station,
	  this time under cold conditions.  During the Cirris
	  continuity tests, four lines showed resistances higher
	  than normal (normal is ~2 ohms), with two ~3.5 ohms,
	  one ~5.5 ohms, and one ~7 ohms.  However, after
	  allowing the feedthrough to warm up and then cool
	  down again, the lines with previously high resistances
	  returned to normal.  The high resistance were presumably
	  associated with the connections.  There are a total of eight 
	  connections per test, four in the bellows and four in the 
	  funnel (including the pigtail jumper) not counting the
	  connections between the Cirris tester and the warm flange.  
	  In principle, the location of a high resistance connection 
	  might be determined with the TDR.  Bench tests indicate that
	  the level (rho) of the TDR trace following a resistive
	  connection (~3 ohms) is noticably higher than normal.
	  However, if the fault occurs well away from the TDR
	  input (ie, somewhere in the cold funnel) we might not
	  be able to resolve it.  It should also be noted that
	  all of the `high resistance' measurements were accociated
	  with PCT pincarriers in FT-1.
	  

*) No sign of the vacuum cables yet.

*) George Stenning (Purchasing Services) is looking into the 
   pincarrier delivery schedule.

*) The remaing warm flanges, all cold flanges, and all unused
   material will be shipped to us from Ebco on May 1.

*) Roy has contacted BOA regarding the delivery schedule of
   the bellows.  They will ship the first 6 bellows next Tuesday 
   (April 25th).

*) Terry has requested a quote on having the resister thermal
   contacts precut by the vendor.  If the cost is too high (it
   probably will be...) it will be a simple matter to cut them
   ourselves. 

*) Margret will attend LARG week next week.  Please supply
   her with any information and/or slides you wish to be
   presented. 

Agenda for next week:
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- Milestones
- Revised pincarrier delivery schedule (TH)
- Missing pigtails/labels
- AOB