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cobeal

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Retained

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  1. Any quality jack when wired correctly conforms to the twist specification. Additionally, unless your jack is in an extremely electrically noisy location the amount of noise is not likely to degrade speed. The pairs and the twists are designed so that the logic on each end can deduce an electrical signal from outside by the nature of the arriving signal. On the pair there will normally be a positive and negative impluse that arrive simultaneously at the receiving end. If an electrical spike traveling through air induces a change in the data in the wiring of the network cable then the received end will see this as a difference between normal and what has been received. In a simplified example if you have a ^ and a V that are supposed to arrive at the same time and a strong ^ is induced into the copper wire at a point in time that ^ (up spike) will push the electrical signal up in both of the pair wires and is easily detected by the logic as an error and not true signal. If you have seen the back of a wired keystone jack that was done by a lazy or uneducated person then you will likely see a length of the pairs outside the outer jacket and without proper twists. This is because the person lacks skill or knowledge. A properly wired keystone jack does not have over half an inch of untwisted wire. I just did some yesterday. The top guard is removed. The ethernet is stripped of outer cover only about 1.25 inches for easy work. The pairs are all untwisted and the cable is laid into the tunnel of the jack with the outer jacket about half way up between the deepest "groove" and the one closest to the edge. The 2 pairs that will go above the center are laid up in that general direction and the 2 destined for the closest to the edge are pulled back in that direction. Next you gently shape the individual wire across the punchdown receptacle paying attention to not pull real hard or leave any slack. Placing the jack on a solid surface you put your 110 punchdown blade into the top with the cutting blade to the outside and if the blade is sharp and the pressure set correctly and the wire is copper then when you push straight down the spring load will snap and push the wire into the correct location at the bottom of the slot and cut the copper wire flush. Do this for each and then push the cover back onto the jack so that the retainer will secure the outer jacket at that middle position in the jack and snap it into the wall plate or wall mount an you will end up with a full spec wired jack. My runs routinely check out to full spec. We run a $1200.00 certifier tool on each installation from the wiring closet to the end of the cable that is plugged into the jacks rather than the jack itself so that we can guarantee compliance right up to the device that will be connected. If you do it like the uneducated, or lazy, or low skill installers then you will not put the cover back on or will do so backwards or without any exterior jacket under the retaining bump and all the pairs will have a couple of inches bared and untwisted. Even those types of installations seem to function fine in most applications because the twists are only present to allow detection of injected signals and if there are no injected signals in the immediate area of the jack that are strong enough to get through the wall plate and the insulation then the lack of twisting has ZERO NEGATIVE IMPACT. Jack problems I have seen most often are those due to failure to use a proper punchdown tool or those that have been reused too many times. On one occasion I did find some speed issue because the client decided to park a refrigerator in front of the wall plate and cause the cable to bend at a radius tighter than the spec allows. A bend in wire is like a kink in a garden hose so either the refrigerator and all of the electromagnetic waves it pushes into the air when the motor starts up or the tight bend or the combination caused the performance to degrade. We moved he refrigerator so I will never know which of the wrong things caused the trouble. It is gone.
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