Talk:Four-wire circuit

grammar
I'm going to edit some tense mistake in the first paragraph. feel free to revert if it's not appropriate. Wilsonsamm (talk) 17:27, 6 September 2008 (UTC)

how it works
why have four wires between two points for full-duplex communication? Surely it is sufficient to have [signal from A to B], [signal from B to A], and [a common ground lead shared by both other wires]. Wilsonsamm (talk) 17:27, 6 September 2008 (UTC)