For the same reason a policeman wouldn't trade in his Kevlar reinforced vest for a nylon one,,just because city council passed an ordinance prohibiting criminals from carrying anything but pellet guns. Dewey > -----Original Message----- > From: Graham Collins [SMTP:[log in to unmask]] > Sent: Thursday, November 08, 2001 11:38 AM > To: [log in to unmask] > Subject: [TN] High Tg FR-4 > > Hello Technet > A question for bare board gurus. Is there a difference in reliability > between high Tg and regular Tg FR-4 ( IPC-4101/24 vs IPC-4101/21) in a > vehicle type application? > The end use application is less than Tg of /21 material, so not in the > glass transition range for either material. > > Typically - is the CTE different between these two? (I expect that > depends on the manufacturer to some degree). If there isn't a high > temperature operating requirement, why select the high temp FR-4? > > Thanks! > > > > regards > > Graham Collins > Process Engineer, > Northrop Grumman > Atlantic Facility of Litton Systems Canada > (902) 873-2000 ext 6215 > > -------------------------------------------------------------------------- > ------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > 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 delivery of Technet send the following message: SET > Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > > E-mail 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 > -------------------------------------------------------------------------- > ------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------