You need to move next door to an AM radio station. You get a given amount of RF power depending on how far away, how many, and your antenna efficiency of the transmitter sources you pick up. From that, you can only transform it to more voltage/less current or less voltage/more current, the product being the given collected power.
High Power UHF television station are very directional in the beam formng. They target their peak radiation lobe 15 to 30 miles out. You will receive less power if you live too close as most of their power shoots over your head. I have a strong FM station about 1.5 miles away that I have to put multiple stage suckout traps to avoid it overloading my TV distribution amplifier. It produces 0.5 vrms across a 75 ohm load on my antenna (3.3 mW's).