My question is in reference to previous posts that asked about the effects of solder mask (or silkscreen) on the impedance of lines for high frequency ( >2 GHz) lines. The general consensus I took was that solder mask could greatly effect the expected impedance of the traces as another dielectric is introduced. In my application we have etched antennas on a 60mil FR4 board.=20 Normally, I have made antennas in house using a simple acid etch bath (crude but effective). However, when we order boards from a PCB house, any exposed traces are normally covered in a layer of solder (including our antennas, but there is no soldermask on the antennas). Now given that solder is not copper and thus it will have different electrical properties, how will this effect the expected performance of the board, and will it be a noticeable effect? Regards, Sean McDevitt Student University of Colorado - Boulder ------------------------------------------------------------------ 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