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Yes, but most of us guys only carry Cat5e on our trucks.

How many kinds are there?


I'm sorry to disagree, but any increase in the number of twists per foot in a voice cable will improve cross-talk rejection. It's just simple physics, and is not subject to opinion, interpretation or debate.

I'm sure it galls people to hear the truth, but the facts are irrefutable. You can prove it empirically, if you're not convinced by the science. Put a test tone across a full pair of Cat3, 5, and 6. Run your probe along the side of each, and tell me which one is loudest.

I'm going to step in and represent Hal by Proxy:

KSU-Less (A.K.A: Self-contained) systems typically are designed to only work within a total station wiring limit of 600 feet. They were designed for 'loop' or 'daisy-chain' wiring that is typically encountered in residential installations.

In situations where individual runs (star topology) are made to each phone, it is very easy to exceed this limit. With six stations, who knows what the total wiring length ends up being?

Throwing CAT5 or above into the situation further complicates things. Due to the much tighter (and unnecessary) pair twists, the length of a cable run is increased dramatically. I believe that I heard that CAT5 increases each inch of cable by three-times what industry-standard cabling for voice would be. A 50 foot run becomes the phones' electronic equivalent of 150 feet!

Keep in mind that these phones weren't designed to work on wiring that isn't based upon typical voice cabling (CAT Zero through three). I'm putting my money on the fact that the CAT5 run(s) have taken this limitation beyond 600 pair feet for the total installation.

For you guys who 'only carry CAT5 on the truck', here is the reason why you are wrong in making the assumption that wire is wire. Let this be a learning experience.

Save yourself some money and do it right with the proper cable for voice.

so you haven't checked for cross talk at the demark ?

that should be step one

distance limitations aside

the question has to be asked , if there are millions of conversations taking place as I type over cat3 or less cross talk free and the signal has traveled miles over cat3 or less to reach the demark cross talk free why the last couple 100 feet need something better

..what about cross talk in the days prior to cat4 ?

I'll stick with my statement "it ought to be CAT3, CAT4 , 5 or 6 will give you no benefit for voice applications "...and as Ed pointed out it may even be a inferior solution

back to the problem at hand I would be pulling all jacks and looking for "shiners "

testing with all phones removed from the lines .

the demark has the tel co lock on it so i couldnt actually do a demark test. but the customer had them come out and they found out the cross talk was on thir end. but im happy to have all this advise to consider next time. thanks dave

Lucky you, davetel. The TELCO X-talk must have been terrible for them to admit it!

The subscriber side of demarks, by definition, are supposed to be available for connection and testing by the subscriber. Maybe you were trying to open the wrong side?

good point, by definition "DEMARK" the point of demarcation subscriber <-------> Telco

Ive never seen a lock on any tel co equipment unless your talking about a security screw

And even the security screw does not prevent entry to the sub side. That side usually is fastened by a "plus/minus" screw.