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Chris, Brad, 802-3-10gbt,
Why are NEXT and MDNEXT calculations skewed in clause 55-Link Segment-release.pdf?
If I take the limits of cable NEXT and two connectors NEXTs and do a power summation I get 1.5 dB to 4.3 dB difference. With MDNEXT the difference is 2 dB to 6 dB, worse at higher frequencies.
I notice the same thing happening in 568-B.2-1 equations (20) and (21).
It does not happen with 568-B.1 equations (5) or (6).
The 568-B.1/ASTM D4566 PSNEXT of equation (7) and the other expressions with factors of ten produces incorrect power summations as well.
It seems to me that all these expressions for power sums should be forming as root-sum-square.
Product Technology Development
Dear Task Force members,
This will be posted on website in a couple of days, but here's a copy now for you to review. Thanks to Chris for putting this together.
Please find attached contribution D1.0 Clause 55 Link Segment specification for posting.
editor: Clause 55.X Link Segment