I read in !emc-pstc that Joe Randolph <[email protected]> wrote (in <[email protected]>) about 'Model for CAT 5 cable' on Fri, 26 Sep 2003:
>I'm interested in obtaining a lumped model, consisting of R, L, and C >elements, for a single pair of wires in a representative section of >Category 5 UTP cable. You could measure a length of cable yourself, if you don't need an officially-certified model. R is fairly easy - measure at DC and calculate any skin effect. C is also fairly easy, but you might have difficulty with L. I have a very good transformer ratio-arm bridge that will do this, but they are not common. One way that may work is to measure the loop impedance, by comparing voltage-drops with that over a known resistance and calculating the inductance from knowing the resistance. You could also resonate the loop with a known added shunt capacitance and measure the resonance frequency, but the Q may be low. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
