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Talk:Balanced line

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differential signals and crosstalk, again

[edit]

"Symmetric differential signals exist to prevent interference to other circuits (crosstalk)[11] - the electromagnetic fields are canceled out by the equal and opposite currents. But they are not necessary for interference rejection from other circuits"

This sentence is not completely untrue, but it creates an incorrect impression that differential signaling is separate from balanced transmission line. In practice these are very closely related, so it's just confusing interested readers. I think it should be removed

If you deliberately feed a signal that is not differential (i.e., has significant common mode power) through a balanced line into a balanced circuit, the differential component of the signal will have good interference rejection, but the common mode component will not. In addition, the crosstalk created by the common mode signal may be far more than what the balanced line is expected to generate.

If it's not deliberate and you don't care about the common mode signal and have good CMRR, you may think it's ok. But then any non-differential component is just a waste of power. So in general, transmitting a non-differential signal over a balanced medium is poor engineering. Laugh Tough (talk) 16:09, 5 November 2021 (UTC)[reply]

Interference rejection depends on the balance, it really is not relevant what the signal is doing. I don't understand in what sense this amounts to a waste of power. Where is signal power being absorbed before it gets to the receiver? Do you have any sources backing up your claims? SpinningSpark 20:11, 5 November 2021 (UTC)[reply]