Ed, My first question is the degradation in shielding effectivenesss compared to what? If you are comparing the conductive epoxy to a screw-fastened connection you need to know the exact resistance of both shield paths. I think if you took a good four-wire resistance measurement box-to-box for a typical cable length you could get a good comparison of relative resistance. If one construction had 5% higher total resistance the degradation would be at least 5% at the lower frequencies.
I've had fairly good success using two multimeters if a 4-wire unit is not available. One provides the current source (on Lo Ohms) and the other measures millivolts. I use large alligator clips with the measurement clips inside of the ones for current. Scott B. Lacey On 16 Jun 2008 at 8:48, Price, Edward wrote: > > I'm curious about the effect of using a gold (or silver) loaded > epoxy to bond a connector shell to a chassis box. If I measured > a bond resistance of about 1 Ohm from the connector shell to > the chassis, how could I estimate the degradation in shielding > effectiveness (frequency range of interest is about 10 kHz to 5 > MHz)? > > Maybe this has been thoroughly covered in some past > Symposium papers. Can anyone give me a hint about where to > look? Of course, absolutely definitive answers, which allow me > to remain lazy, are also quite acceptable. > > Thanks in advance! > > > Ed Price > [email protected] WB6WSN > NARTE Certified EMC Engineer & Technician > Electromagnetic Compatibility Lab > Cubic Defense Applications > San Diego, CAUSA > 858-505-2780 (Voice) > 858-505-1583 (FAX) > Military & Avionics EMC Is Our Specialty > > - ---------------------------------------------------------------- This > message is from the IEEE Product Safety > Engineering Society emc-pstc discussion list. Website: > http://www.ieee-pses.org/ > To post a message to the list, send your e-mail to [email protected] > Instructions: http://listserv.ieee.org/request/user-guide.html > List rules: http://www.ieee-pses.org/listrules.html > For help, send mail to the list administrators: > Scott Douglas [email protected] Mike Cantwell [email protected] > For policy questions, send mail to: > Jim Bacher: [email protected] David Heald: [email protected] > All emc-pstc postings are archived and searchable on the web at: > http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
