That really varies with each stations. Solid state TX's typically are 25W carrier for AM and 100W PEP for SSB. Much of the tube gear can be from 40W to 150W carrier. Then, you have stations with either homebrew, or modified broadcasting gear, (Like Radio Metallica.), that claimed 10KW. And then, you also have small, homebrew, TX's like the famed Grenade that put out around a 10W carrier. So, it varies with every station.