When the FCC mandated making the clarifier a receive-only control, it was with the assumption you'll only be talking to one other station on the channel. And when that's what you're doing, no problem. You tune them in, they tune you in. All is good.
Until a third station comes in and asks why the two of you are on separate frequencies. The accuracy of a consumer-grade CB radio's frequency adjustment won't allow you to sell a CB that's dead-on frequency out of the box every time. Not cost effective.
Decades ago, sideband operators considered themselves separate from the AM crowd. They formed clubs, and would operate on a "club" channel. Frequently these were above channel 23, and later on above channel 40. They would avoid using the CB "10" codes and adopted ham-radio "Q" signals. But sharing a channel with a roundtable of operators required having your transmit frequency the same as everyone else.
Or else.
Turned out they didn't care to have to turn that clarifier knob when you keyed up. 40 years ago it was incredibly common for a customer to request this mod, because a particular group wouldn't come back to him until he got his radio "fixed". He could talk to the sidebanders all he wanted. But if he wanted any of them to answer, he had to transmit on THEIR frequency.
And a quick trip to the ham bands will reveal that they are just as finicky about this as the old-time "freeband" operators.
Oh, wait a minute. That's who populates the ham bands now. Folks who hope you don't know that's how they got into radio.
73
