Phil, By any chance have you measured DK (i.e., dielectric constant)change after a temperature soak. Regards, George George M. Wenger (908)-546-4531 Reliability Engineer RF Power Amplifier Group Andrew Corporation, 40 Technology Drive, Warren, NJ 07059 [log in to unmask] -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Phillip E. Hinton Sent: Thursday, April 22, 2004 12:11 PM To: [log in to unmask] Subject: Re: [TN] PCBA at higher temperatures Larry I have done this temperature soak a number of times with FR4 and do not find any degradation of the assembly properties of the laminate except there is a significant browning of the laminate. It looks like polyimide after baking. There is s slight degrease in the surface resistance when subjected to humidity. However, I have not tested flashover strength or arc resistance after baking. Phil Hinton . --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- ------------------------------------------------------------------------------------------------ This message is for the designated recipient only and may contain privileged, proprietary, or otherwise private information. If you have received it in error, please notify the sender immediately and delete the original. Any unauthorized use of this email is prohibited. ------------------------------------------------------------------------------------------------ [mf2] --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------