I'll weigh in with an it depends. The fabrication process controls the dimensions that affect impedance within a specified tolerance. For example, if the design uses a one inch wide line the effects of line width variation will be minimal (+/-0.0005 inch is =/- .05%). If the design uses a .003 inch wide line the effects of line width will be significant (+/- .0005 inch is 17%). The design needs to be optimized for producability using the process capabilities of the board fabricator to achieve a producable board with a 2% impedance tolerance. Don Vischulis -----Original Message----- >From: Jeffrey Bush <[log in to unmask]> >Sent: Mar 16, 2006 7:59 AM >To: [log in to unmask] >Subject: Re: [TN] Antenna Tolerance > >I agree and much depends on materials, stripline geometry, etc. The 2% >may be outside of PCB processing capabilities - line definition, >etching, plating, etc. > >Jeffrey Bush >Director, Quality Assurance and Technical Support >VERMONT CIRCUITS INCORPORATED > 76 Technology Drive - POB 1890 > Brattleboro, Vermont 05302 > Voice - 802.257.4571 ext 21 > Fax - 802.257.0011 > <http://www.vtcircuits.com/> > > >-----Original Message----- >From: TechNet [mailto:[log in to unmask]] On Behalf Of Lee parker >Sent: Thursday, March 16, 2006 8:48 AM >To: [log in to unmask] >Subject: Re: [TN] Antenna Tolerance > >Selva > >It is possible, but the yield will be very low which will be reflected >in >the cost. You will also find only a few shops willing to accept this >requirement which will again impact price. I suggest you review the >design >and determine if other alternatives are available. How long are the >affected >traces? > >Best regards > >Lee > >J. Lee Parker, Ph.D. >JLP Consultants LLC >804 779 3389 > > >----- Original Message ----- >From: "Selva Suganthi" <[log in to unmask]> >To: <[log in to unmask]> >Sent: Thursday, March 16, 2006 7:48 AM >Subject: [TN] Antenna Tolerance > > >> Dear All, >> >> Is it possible to achieve the electrical impedance of RF antenna to >+/-2% >> tolerance ? >> >> Thanks and Regards >> Suganthi >> "Progress is the activity of today and the assurance of tomorrow." >> >> --------------------------------------------------- >> Technet Mail List provided as a service by IPC using LISTSERV 1.8e >> 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 or (re-start) delivery of Technet send e-mail to >> [log in to unmask]: SET Technet NOMAIL or (MAIL) >> 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/contentpage.asp?Pageid=4.3.16 >> for additional information, or contact Keach Sasamori at >[log in to unmask] or >> 847-615-7100 ext.2815 >> ----------------------------------------------------- >> > >--------------------------------------------------- >Technet Mail List provided as a service by IPC using LISTSERV 1.8e >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 or (re-start) delivery of Technet send e-mail to >[log in to unmask]: SET Technet NOMAIL or (MAIL) >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/contentpage.asp?Pageid=4.3.16 for additional >information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 >ext.2815 >----------------------------------------------------- > >--------------------------------------------------- >Technet Mail List provided as a service by IPC using LISTSERV 1.8e >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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) >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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 >----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------