Oh I remember this station. This was a part 15 station known as “Village Radio Montclair” that used to use multiple low power transmitters to cover a downtown a

Oh I remember this station. This was a part 15 station known as “Village Radio Montclair” that used to use multiple low power transmitters to cover a downtown area, around the turn of the century. I think they were synchronized to create a seamless transition as you left one coverage area and entered another. Or at least that was the goal. It’s the same rule part that allowed for the low power microphone you mentioned. It only allows for 250 microvolts per meter (measured at 3 meters away on the FM band) which is a tiny coverage area. Edit to add: Back in the 1990’s and early 00’s, these signals went much further than they would in 2024, because the FM band had lots of blank spots. With HDRadio sidebands and since-licensed low power repeaters, those blank spots are now filled up.