Twisted pair communications cable with selective separation of pairs

1. A communications cable, comprising:

a cable jacket;

first, second, third and fourth twisted pairs of insulated conductors positioned within the jacket, the first, second, third and fourth twisted pairs having, respectively, first, second, third and fourth twist lengths, wherein a first difference between the first and third twist lengths and a second difference between the second and fourth twist lengths are less than the difference between the twist lengths of any other combination of twisted pairs, and wherein a third difference between the third twist length and the fourth twist length is less than the difference between the twist lengths of any other combination of twisted pairs except for the first and second differences; and

a separator positioned between the third and fourth pairs;

wherein there is substantially no separator present between the first and second pairs, the second and third pairs, and the first and fourth pairs;

wherein the separator is a substantially flat tape.

2. The communications cable defined in claim 1 , wherein the separator is positioned such that an edge thereof is at least partially located between the second and fourth pairs and between the first and third pairs.

3. The communications cable defined in claim 1 , wherein the first and third pairs are positioned diagonally from each other, and the second and fourth pairs are positioned diagonally from each other.

4. The communications cable defined in claim 1 , wherein the separator comprises a material selected from the group consisting of: polyethylene, polypropylene and FEP.

5. The communications cable defined in claim 1 , wherein the jacket has an inner diameter, and wherein the separator has a height dimension that is between about 27 and 82 percent of the jacket inner diameter.

6. A communications cable, comprising:

a cable jacket having an inner diameter;

first, second, third and fourth twisted pairs of insulated conductors positioned within the jacket, the first, second, third and fourth twisted pairs having, respectively, first, second, third and fourth twist lengths; and

a separator positioned between the third and fourth pairs, the separator having a height that is between about 27 and 82 percent of the jacket inner diameter;

wherein there is no separator present between the first and second pairs, the second and third pairs, and the first and fourth pairs; and

wherein the separator is positioned such that an edge thereof is at least partially located between the second and fourth pairs and between the first and third pairs.

7. The communications cable defined in claim 6 , wherein a first difference between the first and third twist lengths and a second difference between the second and fourth twist lengths are less than the difference between the twist lengths of any other combination of twisted pairs, and wherein a third difference between the third twist length and the fourth twist length is less than the difference between the twist lengths of any other combination of twisted pairs except for the first and second differences.

8. The communications cable defined in claim 6 , wherein the first and third pairs are positioned diagonally from each other, and the second and fourth pairs are positioned diagonally from each other.

9. The communications cable defined in claim 6 , wherein the separator comprises a material selected from the group consisting of: polyethylene, polypropylene and FEP.

10. A communications cable, comprising:

a cable jacket;

first, second, third and fourth twisted pairs of insulated conductors positioned within the jacket, the first, second, third and fourth twisted pairs having, respectively, first, second, third and fourth twist lengths, wherein a first difference between the first and third twist lengths and a second difference between the second and fourth twist lengths are less than the difference between the twist lengths of any other combination of twisted pairs, and wherein a third difference between the third twist length and the fourth twist length is less than the difference between the twist lengths of any other combination of twisted pairs except for the first and second differences; and

a separator positioned between the third and fourth pairs;

wherein there is substantially no separator present between the first and second pairs, the second and third pairs, and the first and fourth pairs; and

wherein the separator is positioned such that an edge thereof is located between the second and fourth pairs and between the first and third pairs; and

wherein the first and third pairs are positioned diagonally from each other, and the second and fourth pairs are positioned diagonally from each other.

11. The communications cable defined in claim 10 , wherein the separator comprises a material selected from the group consisting of: polyethylene, polypropylene and FEP.

12. The communications cable defined in claim 10 , wherein the separator is a substantially flat tape.

13. The communications cable defined in claim 10 , wherein the jacket has an inner diameter, and wherein the separator has a height dimension that is between about 27 and 82 percent of the jacket inner diameter.