All other FMs in Louisville are 50,000 watts or less. Several are Class A, maximum 6,000 watts. So how did WAMZ become a Class C station with a 100,000 watt signal?
It was originally WHAS-FM, co-owned with Louisville's AM powerhouse, WHAS 840, and dominant daily newspaper, the "Louisville Courier-Journal." It signed on in 1966, after rules about FM power had been established. So it's not like it was grandfathered at the high power it now enjoys.
The key is where Louisville placed its TV towers. It was cheaper to locate those towers on the other side of the Ohio River in Indiana, towers which could also be used for FM radio. The land was undeveloped and elevated, putting a good signal over Louisville and its suburbs. But for FM stations, there was a big difference between Indiana and Kentucky, something that TV stations didn't have to worry about.
Kentucky is in Class C territory but Indiana is Class B. So if a broadcaster put its FM transmitter on a TV tower in Indiana, the maximum power is 50,000 watts. Most broadcasters did it anyway but not WHAS. It put WHAS-FM's tower in Kentucky, allowing it to run 100,000 watts. Just for the record, the class of an FM station is determined by where the transmitter is, not the city of license.
It was originally WHAS-FM, co-owned with Louisville's AM powerhouse, WHAS 840, and dominant daily newspaper, the "Louisville Courier-Journal." It signed on in 1966, after rules about FM power had been established. So it's not like it was grandfathered at the high power it now enjoys.
The key is where Louisville placed its TV towers. It was cheaper to locate those towers on the other side of the Ohio River in Indiana, towers which could also be used for FM radio. The land was undeveloped and elevated, putting a good signal over Louisville and its suburbs. But for FM stations, there was a big difference between Indiana and Kentucky, something that TV stations didn't have to worry about.
Kentucky is in Class C territory but Indiana is Class B. So if a broadcaster put its FM transmitter on a TV tower in Indiana, the maximum power is 50,000 watts. Most broadcasters did it anyway but not WHAS. It put WHAS-FM's tower in Kentucky, allowing it to run 100,000 watts. Just for the record, the class of an FM station is determined by where the transmitter is, not the city of license.