A recent GETEC presentation showed the following information for the range of 800 Mhz to 2 Ghz: GETEC 3.8 BT/epoxy 4.0 Teflon 2.2-3.5 FR4 4.2 Our local rep covering the Arizona area for the General Electric materials is Jeannie Newhart. Her e mail address is [log in to unmask] ---------- From: [log in to unmask] To: [log in to unmask] Subject: Re: Fabrication Date: Wednesday, September 04, 1996 7:03PM I have seen data to suggest the difference between 1 Mhz to 1 Ghz is ~10%. Like standard FR-4 is ~4.5 @ 1 Mhz and ~4.1 @ 1 Ghz. I haven't seen values at 2 Ghz. Some materials have a flatter response across a larger (BW) range of frequencies. This means that they have less electrical performance variation(degradation) from say 1 Mhz to 1 Ghz. Some of these materials are Getek, BT, Cyanate Ester, and alternative glass fiber styles (random aramids). Remember there is a cost associated with the higher performance materials. One thing I do know is that not all material manufacturers have ran these Er tests at different frequencies. The exotic material suppliers have, but not all the standard FR-4 makers. We (fabricators) have constantly been asked this question by our customers and have requested this type of testing from our material suppliers. Few have responded. In order for their materials to even be considered for an RF design they need to at least do their homework. The other materials provide a "slight edge" electrical performance wise and those suppliers have targeted this market with their Er and Df results at various frequencies (as you've requested). Wake up call! Groovy ______________________________ Reply Separator _________________________________ Subject: Fabrication Author: [log in to unmask] at SMTPLINK-HADCO Date: 9/4/96 6:05 PM From: Scott B. Westheimer Date: September 5,1996 I am looking for information about the Dk of material measured at 1 mhrtz and measured at 1 and 2 ghrtz. What would be the expected change? Does anyone have an article that they could send me are direct me too? Are any of you PCB end users requiring that boards be measured at 1 to 2 ghrtz? Thanks *************************************************************************** * 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. * *************************************************************************** *************************************************************************** * 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. * *************************************************************************** *************************************************************************** * 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. * ***************************************************************************