SEMTTP said:
I believe that the CB rules are you cannot construe your message. So having Encode/Decode on a CB would be illegal. Besides, in order to put Encode/Decode into a CB radio of any sort would require modfing the radio. Again that is against the rules.
You dont seem to have a solid understanding of what tone squelch is. How does using a tone squelch, or some other type of selective calling "construe" your message? There is no privacy provided by using tone squelch, other people on the frequency will still hear what is being said.
Also, adding a selective calling function does not require making any internal modifications to the radio. Everything can be added externally.
If you dont want anyone to hear your conversations, perhaps dial your CB radio back down to 4 watts and use a different channel.
Where did anyone say anything about running higher levels of power, and what does that have to do with anything?? Trying to stir the pot?
Besides, having Encode/Decode would be a rediculous function to have in a CB radio. Encode/Decode was not designed for CB. If you want privacy there is alway the telephone, otherwise enjoy the airways that is why they are called CITIZENS BAND!!
C'mon..get real people. Please do explain why it would be a "rediculous function to have in a CB radio." I think it would be a great function to have, and there is nothing wrong with what CSL126 wants to do.
FYI....There is a specific section in the part 95 rules/regs that ALLOWS the use of selective calling. The only restriction being that audible tones can only be transmitted for a short period of time. Subaudible tones can be transmitted continuously. If you dont believe this, please do spend a few minutes and browse the regs at fcc.gov.
However, I must add that the use of CTCSS on CB is generally unreliable. Due to the nature of AM, beat tones created when multiple signals are present at the receiver will often cause falsing. It will work, but don't expect a great level of reliability. (as grem was saying)
Although I am not aware of any currently available "plug and play" options for CB, it wouldn't be terribly difficult to implement. Audio can be injected at the micropone input, and the decode end can be connected to the external speaker output (perhaps with a relay to provide the "squelch" function). Of course, if the frequency response of the TX/RX audio stages have a high pass cutoff which would filter subaudible tones, you may need to use tones in the voice range. In this case, there are DTMF encoders and decoders available (ramsey has one I think) that could work as well.
Good luck and have fun!
-Jim