Radio stations can be tuned in to with the Pip-Boy 3000 in the Capital Wasteland. Other radio signals can be found that are related to quests. While the sounds of the radio resonate with the local environment, it does not affect the 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, one must be in a certain range or the Pip-Boy 3000 won't pick them up. At the beginning of the game, Galaxy News Radio is only available in some regions around Washington D.C. One must complete the Galaxy News Radio quest for it to broadcast across the entire Capital Wasteland. Also, Agatha's Station radio signal is unable to be picked up until the quest Agatha's Song is completed.
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. These radio signals will become clearer the nearer one gets to the ham radio, not the tower that broadcasts the signal.
During the quest Tranquility Lane, when entering a house, sometimes a message in the top-left corner will say, "(Radio station) signal found", but one is unable to look at or listen to this station because they can't access the Pip-Boy 3000 in the simulation.
If Raven Rock is destroyed, Enclave Radio will be lost. If Broken Steel is downloaded, the loss of the aforementioned radio station is unavoidable, as Raven Rock will be destroyed by the Brotherhood of Steel if the Lone Wanderer has not done so already.