Those multi-tower setups are usally driven by serious amateur radio operators, often hobbyists who are quite skilled at antenna design and site preparation. What you saw is likely a complex HF or VHF network built out on a large rural parcel of land. These stations aren't typically running low-power casual operations; they are usually part of an advanced digital data or high-frequency communication group. The sheer scale suggests a dedicated effort far beyond a backyard hobbyist unless that person has exceptional resources and space. Regarding zoning and FAA clearance, it's complicated because it depends entirely on the specific local municipality and state laws, especially since you're on a back road. In rural areas, the rules are generally much looser than in suburban or urban centers, but nothing is truly exempt from regulation. Taller structures always require attention to the local planning department rules, and if they exceed certain heights, especially near airports, FAA notification is standard procedure for safety. Many operators simply operate within the allowed limits for a home setup, but building something that big usually requires some kind of paperwork, even if it's just a simple application for a temporary structure.
For power, those arrays require substantial electricity. A home rig pulling a few hundred watts is one thing, but managing power for multiple high-output transmitters and the associated cooling and digital processing units means the electrical service has to be upgraded significantly. A home electrician would need to install dedicated circuits and appropriate service entrance equipment to handle the draw safely, especially if they are running all those towers simultaneously. They are effectively building a small, sophisticated communications facility that happens to be located on their farm. They likely operate as a collective where several individuals contribute to the setup and maintenance, sharing costs and expertise across the different antenna arrays. The setup is a mix of practical engineering and deep technical passion.