General comment
editThis article is just wrong in so many ways. Diplexers are not splitters. They are not baluns. The power issue is lost. It has some good examples, but the technical details and the technical merits of diplexers are buried or lost. Glrx (talk) 05:32, 4 January 2008 (UTC)
Diplexer/duplexer
editThere is some confusion between duplexer and diplexer here. A duplexer is to provide duplex (two way) communication over a single path. A diplexer is to allow two signals to be carried over a single path - i.e. to provide two-channel multiplexing. Generally a diplexer consists of a pair of filters with non-overlapping pass-bands, so it implements frequency-division multiplexing. I agree that a device can be both a diplexer and duplexer - if it is a diplexer where the two signals travel in opposite directions (as in the diagram). However this does not mean that diplexer and duplexer are synonymous. A circulator is a duplexer but not a diplexer. A filter that splits or combines two signals occupying separate frequency bands is a diplexer but not a duplexer. --catslash (talk) 00:39, 3 October 2009 (UTC)
