Interesting idea, and the stick and transmitter we have has enough bandwidth to pull it off, but there's two drawbacks:
- That kills the analog signal, thus doesn't work on a normal radio, only HD radios. Being on AM is already a disadvantage. Being nothing but noise on most radios would be suicide.
- It would involve not only having to pay for expensive new gear, but fees for using the system. Add to that trying to explain it to clients.
"Not only is it AM radio, but it's AM radio that you need a special kind of radio to hear. How may spots can I sign you up for?" That's not going to work.