Michael, I use the 3-parameter Weibull plot in an MS Excel program to simulate PTV reliability in PWBs under various thermal cycling scenarios. It predicts mean fatigue life of plated-through-vias and is largely based on IPC-TR-579 [Engelmaier, et.al.]. I have experimented with various shape factors but usually use alpha=3, which skews the probability curve just left of normal. Given about a dozen input parameters of the PWB, it generates two graphs: (1) Weibull cumulative distribution and (2) Weibull failure probability density. If I can be of further assistance, please reply directly via e-mail. Joe Felts -----Original Message----- From: Michael Becker [SMTP:[log in to unmask]] Sent: Tuesday, April 13, 1999 7:52 AM To: [log in to unmask] Subject: [TN] Anatech box/3 parameter Weibull 1)Does anyone have a contact at Anatech(analysis Technology) or have an Anatech Box for rent or lease available for a short period of time?(<2 months) 2) Does anyone have experience with a 3 parameter Weibull plot? Please email me at [log in to unmask] thanks, Michael ################################################################ 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################