Total posts : 45366
I would strongly recommend that you test out 1 Rangemaster in the locale in which you hope to broadcast, installed in the manner you hope to do with all of them. That will give you an appreciation for the potential range of a listenable signal, which is key. And what you need to receive it, either with a car radio or a home radio.
While it’s certainly possible to get a range of 1 to 1 1/2 miles with Part 15 AM, there’s going to be a whole lot of fringe reception in there due to interference, both natural and man-made.
In my experience, I usually count on (with a well thought out, legal – at least in my opinion – installation) 1/4 to 1/2 mile of strong and listenable signal to a good AM radio. I can get a listenable signal in my car (and a good home radio) out to a mile in some directions, but in others I wouldn’t want to listen for any length of time at all.
And as advised in an earlier post, I would investigate the problems other installations have had, particularly with legality. Any attempt to cover the kind of radius you’re looking at will receive a great deal of scutiny, both from licensed stations and the FCC.
Again, I would experiment before making any expensive commitments.