| abstract |
A plenum cable having a plurality of twisted pair conductors with at least one pair having a non-fluorinated polyolefin insulation and all of the twisted pair conductors which are adjacent to each other having a lay length of about 0.4 to 4'' with the preferred lay length being 0.4 to 1.25 inches. The lay length of the non-fluorinated polyolefin twisted pair conductor is preferably 1.0 to 1.25 inches and the lay lengths of the fluorinated polyolefin twisted pair conductors is preferably 0.5 to 85''. The twisted pair conductor insulation is preferably radially joined along the entire length thereof. Preferably, the twisted pair conductors all have an impedance of 90 to 110 ohms and the impedance does not vary by more or less than +/-0.05 of an average impedance. Also, the twisted pair conductors preferably have a center-to-center distance that does not vary by more or less than +/-0.03 of an average center-to-center distance. Also, for another embodiment, all the adjacent twisted pair conductors have a dielectric constant within +/-0.25 of each other. |