Yes, it can. First you need to make the trace in open condition at the end of the trace then use 50ohm cable to probe to the trace. Yours Sincerely.=20 Mandy_Tsai=20 High Tech Computer, Corp.=20 System Architecture Logic Design / SI Team TEL:+886-2-89124138 Ext: 8244=20 Fax:+886-2-89124136=20 E-mail : Mandy_Tsai@xxxxxxxxxx -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of Kenny Frohlich Sent: Thursday, August 24, 2006 1:00 PM To: geethukarrthik@xxxxxxxxx; si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: PCB impedance coupon measurement Hi all, Since we're on the subject of PCB impedance coupon measurement, I have a question on TDR test. I understand that TDR test is performed at the impedance coupon on the PCB. Can a TDR measurement be taken on an actual trace on the PCB? If a net is routed as a T-topology, can a TDR measurement take on this net? =20 Thanks, Kenny Geetha Balasubramanian <geethukarrthik@xxxxxxxxx> wrote: Dear Members, Generally what is the frequency range for PCB impedance coupon measurement? Is it possible to measue the impedance of the coupon at a specific discrete frequency? For better accuracy is it necessary to have 2 seperate bands one for USB full speed (12 Mbps) design and another for USB high speed (480 Mbps) design? Thanking you all in anticipation Geetha --------------------------------- Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1?min. ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at:=20 //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu =09 --------------------------------- Want to be your own boss? Learn how on Yahoo! Small Business.=20 ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: =20 //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu =20 ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu