Why is is not feasible to use the same frequency for Radio 4 on a nationwide basis?
Q. Hope you don't mind me emailing you so feel free to ignore this if you wish. If you don't, I wonder if you could help me. Why is is not feasible to use the same frequency for Radio 4 on a nationwide basis?
I'm not sure I understand your question. Radio 4 sounds like an English broadcasting service, perhaps? In general most AM and FM broadcasting stations are limited to a certain power so that they don't interfere with other broadcasting stations in nearby cities. Each city has to be able to carry their own local radio programming or the public is not served. So you have dozens of stations, perhaps hundreds, all sharing the same frequency across a country. It would then be impossible for one frequency to be set aside for one station. This is actually a country wide example of frequency reuse, the defining principle of cellular (internal link). Let me know if this is not what you are talking about.