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 ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################