Hello Ginny: I would suggest that the layer in question is not coated with oxide. The next layer down (assuming it's a plane) did receive an oxide coat. Charlie McMahon Genny Gibbard wrote: >Hi, >We just received a new rev of a PWB in house. It has not been populated >yet. It looks like it has been built correctly - the right layer order, >connections, etc - but it looks different than the rest of our 4 layer >boards. Normally the traces on the inner layer that is closest to the >surface appear dark in colour and the deeper layer appears lighter. This >board is the opposite. The layer closest to the surface is light in colour >and the deeper layer is dark. Also, the FR4 seems much easier to see >through than usual. > >Any thoughts or explanations for this? >Thanks for your time. > >Genny Gibbard (mailto:[log in to unmask]) > >--------------------------------------------------------------------------------- >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 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 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 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 ---------------------------------------------------------------------------------