EDIT: Goofed on the title, should have said decreased SNR (signal to noise ratio) instead of attenuation. Apologies.
Twisted pairs are a critical part of any stranded cable. The cables ability operate at high speeds requires exact winding of each differential pair.
I found a Stack Exchange thread discussing whether an even or odd number of twists is better. One answer stood out:
The amount of magnetic interference is proportional to the area between the two wires. With a perfect even number of twists the area is effectively zero. With an odd number of twists it is essentially one twist area. That is still a vast improvement over no twist at all :)
I assume a patch panels is equivalent to the removal of several twists in a twisted pair. Even when artfully installed (with the specified 1/2 or less exposed strands) at least one twist has to be removed. Also, there are the pins inside the port of the RJ45 jack which run parallel to each other.
All of this must culminate in some measurable attenuation/decrease in SNR.
I'm wondering exactly how negligible is this? Say use 3 patch panels are run in series; each placed a few feet apart. Would this have a measurable effect on the cables ability to carry Gigabit traffic?
In optical networks we always have optical budget (often topping out at about 3 Decibel of loss). I don't often hear talk of loss budgets in copper cabling though.
How concerned should I be about splices, ports, or any interruption to the winding of each differential pairs?
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