In message <ofedd17edf.1820b75c-on85257488.004822f4-85257488.0048b...@lexmark.com>, dated Wed, 16 Jul 2008, Rob A Oglesbee <[email protected]> writes:
>We've seen them change insertion loss dramatically by several dB just >by moving them a little bit. They then gradually drift back to >nominal. It's probably a mismatch loss, caused by deformation of the dielectric, not a resistive loss. Once the deformation relaxes, the mismatch disappears. The dielectric materials commonly used tend to relax rather slowly. Some materials and constructions, however, relax much more quickly. It would be very useful if someone with appropriate facilities could do some measurements of this effect and write a paper. Temperature is a factor. Maybe the manufacturer of the cable claiming the fastest relaxation would fund the exercise. (;-) -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Either we are causing global warming, in which case we may be able to stop it, or natural variation is causing it, and we probably can't stop it. You choose! John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - 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
