This is a tough question. First I would have to know if this is a "sellable"
item to the government. If it is, I don't think you can get away with it. But,
if it's a prototype part, or a limited production part, you could write
waivers. I wouldn't want to toss the part IF IT MEETS IMPEDANCE.

But, did your company personally do the impedance test, or see the
actual "lot" data for impedance testing, or are you taking the vendors
word for it? If you have actually tested it, and it's ok, WOW that's great!
But, another question: how come you weren't notified by your fab house
that the board might come in undersized? The houses I have dealt with
have enough knowledge to ask me to verify if they think there is even
a remote chance of not meeting the specified requirement.

Good luck,


Mitch Morey
# Sr PCB Designer #
ComStream Corp
San Diego, CA 92121
Phone: (619)657-5338
Fax    : (619)657-5408
EMAIL: [log in to unmask]

                               ||||||
                            ((o o))
___________oOO_(_)_OOo_____________________

 PCB layout is like fine art. You have to DIE to be famous!
_____________________________________________
                            (_)   (_)

>>> Ken Patel <[log in to unmask]> 02/19/98 03:45pm >>>
This is hot as we have to make a decision...
What will be the impact if the thickness of the fab we received from the
supplier is smaller due to prepregs issues than what we have specified
on
the drawing but within the impedance specified? I mean any other
electrical
issues and not mechanical ones I should be aware of.

Also to correct the problem, is it advisable to change the prepregs from
two
2113 prepregs to 2113+2116 combination. Any problem due to different
material combination.

Thanks in advance.

re,
ken patel
______________________________________________________
Ken Patel                       Phone:  (408) 490-6804
1708 McCarthy Blvd.             Fax:    (408) 490-6859
Milpitas, CA 95035              Beeper: (888) 769-1808

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