A repeater's footprint is a function of the following:
Antenna height
Receiver sensitivity
Effective radiated power output
Shit, forgot the sauce…
https://www.ntia.doc.gov/page/2011/united-states-frequency-allocation-chart
Well, I know that, but I wasn't talking about digital modes, analog only, and was trying to keep things relatively simple for newhamanons.
Also hamradiofag here, can answer some questions.