sequential (73) RJ45 (protocol) center tap (clock line)

https://kamchihau.blogspot.com/2023/07/blog-post.html

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Ref: https://chihaukam.blogspot.com/2025/11/miuson-is-person-in-this-link.html?m=1.

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John : See the 1st picture.  When receive is at Down cycle, transmit is at Up cycle.

Me: Ok.

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John : See the 2nd picture.  When the Transmission is at Up cycle,  the direction current's flow of Tx+ is clear. However,  the direction of current's flow of Tx- is unclear. 

Me: Why ?

John: Because,  it's a common mode which block the current's flow of TX -1.

Me: Same thing.  When Transmit is at the Up Cycle,  the Receive is at the Down cycle. While the Receive is at the down cycle, the current flow of RD+ is clear but the current flow of RD- is unclear because of the common mode.