looking for a place to start..wireless radio 2109

Well in North America, one can use license free devices, but they have to conform to quite limited specifications.

Design doesn't even come into play. It is so much higher in frequency than the FM broadcast band (which in turn is quite a lot higher than the AM broadcast band) that there's nothing there to rework to lower frequencies. It would be like using an apple to make an orange.

The issue isn't "civilian broadcast frequencies" but that the radio spectrum is allocated by service in order to prevent interference between them. The broadcast bands are no more protected than any other service, they are all protected from operation that doesn't belong.

On the other hand, the wi-fi cards are using frequencies set aside for unlicensed operation. Their operation, at least in North America, are under the same sections of the radio rules that allow for very low power transmitters on the AM and FM broadcast bands. And given that wi-fi is used beyond North America, there must be similar rules there.

It seems like some of the confusion of the original poster is because there do seem to be commercial units that do this. Basically they are small computers that might look like radios, which have wi-fi capability, but their intent is to allow for remote listening to audio files from the main computer. But these are using wi-fi.

There's be no difference from any other wi-fi use, if you can transfer a file from your main computer to your lap-top in the living room using wi-fi, then you can (if you are willing to set up a dedicated computer with wi-fi to do it) use it for streaming audio files to a remote system.

Michael