Why don't they make CB's with tone and digital squelch capability ???
They tried that *YEARS* ago and it didn't sell very well. I remember playing with both the Johnson and Courier systems.
The Johnson system plugged in via an octal plug and you could choose between a couple different `tones' along with a couple different `alert' functions like honking the vehicle horn, flashing the vehicle's lights, or sounding a beeper inside the vehicle.
The Courier system was a tad bit fancier in that you ordered it as an `upgrade accessory' to the radio and it came built in. It also used the same `reeds' that the commercial radios used so one had a much larger selection of what `tones' one could use. It did also have an `alert' function that one could wire into either the horn or the lights.
Unfortunately, both systems required extra expenses on top of the initial cost of the radio and in the installation so, except for a very few individuals and business, never really sold all that well. In the all the years I worked for the one local radio shop we only sold about 2 - 3 systems of either brand. The main reason I got to `play' with either one was that it was the way we could demo them. IE: The owner and I each had base units, along with the shop, and mobile units in our own `personal' vehicles. (He had a Johnson system and I had the Courier system. And, yes, even though they both used basically the same `reeds' they weren't compatible with each other. [Sound familiar?])
I can remember taking a prospective customer out for a `test drive', showing off the various `features', and then trying to explain how they would work for them on the drive back to the shop where we would then have to tell them how much more it was going to add to the `base' price of the radio. Usually they would just end up buying the `basic' units without the `added extras' rather than the ones that either had the ability to have them added *in* or *to* the unit. (BTW, you have to also remember that these both were tube units and adding the `tone squelch' option meant a much bigger unit or more pieces to have to deal with.)