Radio stations can be tuned in to with your Pip-Boy 3000 in the Capital Wasteland. Other radio signals can be found that are related to quests and lead you to treasure. While the sounds of the Radio resonate with the local environment, it does not affect your Sneak skill.
Only Galaxy News Radio and Enclave Radio can be accessed right away from coming out the vault. All other signals (like the signals obtained from various power stations all over the map) must be discovered or the appropriate quest completed.
Galaxy News Radio, Enclave Radio and Agatha's Station are broadcast across the entire Capital Wasteland; for all others you must be in a certain range or your Pip-Boy 3000 won't pick them up. At the beginning of the game, however, Galaxy News Radio is only available in some regions around Washington D.C. You must complete Galaxy News Radio for it to broadcast across the entire Capital Wasteland. Also Agatha's Station Radio Signal is unable to be picked up until you complete the quest Agatha's Song.
The "Morse Code Signals" (see temporary signals) all can be decoded to decipher a message, and they must be turned on at the towers they are being broadcast from.
Strangely, these radio signals will become clearer the nearer the player gets to the ham radio, not the tower that broadcasts the signal.
During the quest Tranquility Lane, when you enter a house, sometimes a message in the top-left corner will say, "(Radio station) signal found", but you are unable to look at or listen to this station, because you can't access your Pip-Boy 3000 in the simulation.