Total posts : 45366
Don’t work yourself up over the 200 ft. thing. That came from a notice put out some 15 years ago IIRC, based on the original Part 15 rules from 1934. Who writes blurbs for the FCC might not even recognize details in citing their own regulations. As for FM, well, that is a field strength issue. Range, then, like AM, is often a function of receiver selectivity and sensitivity.
So … if someone points out that FCC page, you should just clarify that reception distance … range … varies widely with individual sense of what constitutes a clear signal, and for AM, modulation, atmospheric conditions, time of day, ground conductivity, and on the quality of the receiver. Therefore, considering the nature of the beast, setting a reception range of AM radio is a relative, indeed almost arbitrary, thing. Radio engineers know that.
For example, in my case, a daytime signal can barely be heard, let alone be clear, on a cheap clock radio at almost any distance, a decent car radio varies from 700′ to a mile (occasionally more), a $5000 communications receiver, filtered, with frequency-tuned preamp, and longwire (300′) outdoor antenna can receive it with good clarity at about 9 miles along the coast. Of course, after sundown, skip makes for much more noise in the AM BCB, so the practical listening area of usable signal decreases.
Ease your mind. In any case whatever, the main points to consider and avoid are interference with licensed stations and grossly illegal physical characteristics of the installation.