I’m wondering... does it make a technological difference on what frequency a given radio station operates?
Since stations have different powers or even direction signals based on their frequencies (to avoid interference with other stations), it can. I think both 98.5 and 104.1 cover similar areas but who knows.
On FM “power and tower” make differences for outreach—how high the antenna is as well as power (the “50,000 watts” a stations boasts of is really an _effective radiation power_
based on these two variables)
Of course. Apart from regulatory issues, each frequency band has different propagation and interference characteristics.
Most of the differences between individual stations in the same band are due to primarily to antenna siting and power levels.
AM, from 540 -1700 kHz can literally go around the world at night, which is good thing, except that it means interference from lighting, other stations and industrial sources couples in from around the world. During the day propagation is much more restricted and many stations have lisences that allow them to transmit with 10X more power during daylight hours than at night. [... skipping physics lesson ...]
FM from about 88 - 108 MHz uses much shorter wavelengths. These frequencies propagate pretty much "line of sight" with a little bit of "ray bending" allowing you to recieve them slightly beyond the geometric line of sight to the antenna. They are much less susceptible to many types of interference, especially from power line transformers, dimmer switches, engine ignitions, lightning strikes, inter al. Because they are line of sight, they are much less susceptible to distant interference.
Microwaves, like those used for satellite television, are even more "line of sight" than FM. They also suffer from an impairment that FM doesn't, rain attenuation. Signal level loss when traveling through rain is proportional to the fourth power of frequency! ("Rayliegh scattering"). Anyway, the upshot is that signals at satellite TV frequencies, which are about 100X greater than FM, suffer about 100,000,000 (100^4) times more loss when traveling through rain. Bad as that sounds, total loss rarely exceeds a factor of four for satellite TV signals. In the United States this occurs about 0.3% of the time. Typcially, home satellite systems are engineered with about "six dB" (4X) of "link margin" meaning that satellite TV providers boast 99.7% availability. (As opposed to broadcast TV which is near 100%).
The issue gets more complicated with Radar, but short story is, the longer the search range, as a rule, the lower the frequency. Space track radar tend to operate near 450 MHz, Air Route Surveillance (long range ATC ~250 NMI) around 1000 MHz, Air Port Surveillance Radar (~ 60 NMI) around 2300 MHz, airborne radar ( ~10 NMI) at 10,000 MHz.