As Simple As Simplex?

(Apparently not)


Anyone who has passed by the UHF/VHF Repeater frequencies have heard when two Hams have been having a one-on-one contact for a while and the sense that they are “hogging” the Repeater suddenly occurs to them. “Let’s go to “simplex” Charlie?” Hell, there are band plans with suggested Simplex frequencies as well as a Simplex National Calling Channel…


It’s a shame that the FCC doesn’t allow Amateurs to operate in real “Simplex” mode!


True simplex operation refers to the type of activity that broadcasters do all the time – it is only one way communication, there is no “back and forth”

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What we Hams use is more accurately called Half Duplex, in which both operators can alternately transmit and receive, but not do so simultaneously!

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I think we all already know what Full Duplex is, we use that method on our telephones everyday. How else would we be able to interrupt the guy on the other end when he starts rambling on…

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Why have Hams (and Hams alone) erroneously called half-duplex operation simplex? Perhaps a long time ago, someone just got it wrong and his fellow Hams didn’t want to correct him and make him feel bad… No, that can’t be right! I think the Ham world uses simplex and duplex to describe the use of single (simplex) or double (duplex) frequencies, while the rest of the world is using them to describe one-way directionality (simplex) or two way simultaneous directionality. It’s probably way too late to try to fix it, but youz guyz should just know, for the record, that you are operating half duplex when you think you’re operating simplex!

Just remember:

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– The Editor –