I doubt it - The whole purpose of a guard trace, as I understand it, is to provide electrical shielding to prevent crosstalk [undesired electrical coupling]. Personally, I don't see how residue of any kind (except metallic) could reduce the effectivity of a guard trace. If there is a problem, it is likely a design issue. IMHO. Denis Lefebvre, C.I.D. Senior PCB Designer Finisar Corporation 1308 Moffett Park Drive Sunnyvale, CA 94089-1133 (408)542-3832 http://www.finisar.com At 09:09 AM 12/7/2001 +0100, you wrote: >Hi All, > >I am after information on Guard Traces. Is there any information / paper on >the reliability / effectivity of a guard trace being reduced due to no-clean >flux residue. > >Thanks for your help. > >Best regards > >Marc. > >--------------------------------------------------------------------------------- >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 the following message: SET >Technet NOMAIL >Search previous postings at: www.ipc.org > On-Line Resources & Databases > >E-mail 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 >--------------------------------------------------------------------------------- > --------------------------------------------------------------------------------- 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 the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------