From another dated (and gray-haired) one - Mark - I believe that what you think might be vias in Fig. 7-17 are simply dots placed in the drawing to indicate locations of the reference numbers for the various discontinuities in the plots. There are no dots in the radius bends because there are no discontinuities in the second plot (c) to be referenced to trace locations. Take a look at Fig.7-15, for example. The dots 1, 2, and 3 tie locations in the trace layout to discontinuities in the waveform; in particular. in this figure there is no rationale for interpreting the dot designated "2" as a via. Regards - Bill Dr. F. Williams Sarles Tel: 781-862-0607 Consulting Engineer Fax: 781-861-7518 FWS ENGINEERING Email: DrFWS@xxxxxxx 54 Ledgelawn Avenue Lexington MA 02420-3449 ------------------------------------------------------------------ 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: http://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: http://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