Here's some information on high frequency values I believe to be fairly reliable. Based on 4-ply 7628 glass (28-mil). Still some variability (just like all things): Freq. FR-4 Getek 1 MHz 4.6-4.7 3.6-4.2 2 GHz 4.5-4.6 3.91 4 GHz 4.4-4.5 3.90 6 GHz n/a 3.88 Glenn Pelkey Quality/Reliability Engineer Maxtek Components Corp. *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************