Does anyone have knowledege of maximium operating temperature for FR-4 PCB's. I've got a board with resistors getting over 200 F with an ambient temperature of 72 F. I'm concerned about the board temperature when ambient gets to 150 or 160 F. www.acculam.com/s2.htm says 285 F is max. Comments appreciated. Scott --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------