AFAIK that radios aren't usually that powerful (at least, legally to non-commercial use), and usually amplifies the modulated signal from the machine, they does

AFAIK that radios aren't usually that powerful (at least, legally to non-commercial use), and usually amplifies the modulated signal from the machine, they doesn't have an input of a direct signal to amplify and send. Anyway, I think you can send signals in baseband from the computer or the SDR and let the radio modulate it.