While you have a good question, Ethernet over twisted pair is rated for use up to 100 Meters. At such short lengths, no one would take time to measure signal loss.
Bob
At what length, if any, does the signal dissipate when running an ethernet cable to a wifi connection. Wanting to put my airport express in my attic, wanting to know if there is a difference between 15ft. and 20ft. in regards to signal.
Thanks,
JJ

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