Hi All, With regards to how a vias capacitance varies with the finished hole size, is there a formula to calculate this? We intend to reduce the via dimensions from 10 mils to 8 mils on a via-in-pad via. The concern is that in RF circuits this has been used for a reason and we are getting kick back due to the concern that the capacitance of the via is being modified. Thanks for your help. Best regards Marc Cowen --------------------------------------------------------------------------------- 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 e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/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 ---------------------------------------------------------------------------------